Molecular spectroscopy III: Nuclear Magnetic Resonance (NMR)

Size: px
Start display at page:

Download "Molecular spectroscopy III: Nuclear Magnetic Resonance (NMR)"

Transcription

1 Molecular spectroscopy III: Nuclear Magnetic Resonance (NMR) Nuclear magnetic resonance (NMR) is a physical phenomenon in which magnetic nuclei in a magnetic field absorb electromagnetic radiation at a specific resonance frequency which depends on the strength of the magnetic field and the magnetic properties of the isotope of the atoms. NMR is also routinely used in magnetic resonance imaging (MRI) Nobel prizes: 1. Nuclear magnetic resonance was first described and measured in molecular beams by Isidor Rabi in 1938, and in 1944, he was awarded the Nobel Prize in Physics for this work. 2. In 1946, Felix Bloch and Edward Mills Purcell expanded the technique for use on liquids and solids, for which they shared the Nobel Prize in Physics in Richard R. Ernst received Nobel Prize in Chemistry in 1991 for his contributions towards the development of Fourier Transform nuclear magnetic resonance spectroscopy. 4. In 2002 Kurt Wüthrich shared the Nobel Prize in Chemistry for his work with protein Fourier Transform nuclear magnetic resonance in solution.

2 neutron Hydrogen (contains 1 proton) Deuterium (contains 1 proton and 1neutron) Note that two very common nuclei, 12 C and 16 O, have zero spin, hence zero magnetic moment: they are invisible in NMR The range of typical chemical shifts for 1 H resonances The 1 H NMR spectrum of ethanol. The bold letters denote the protons giving rise to the resonance peak, and the step like curve is the integrated signal.

3

4

5

6

7

8

9

10

11 Origin of the shielding constant Electron density around the nucleus studied Neighboring chemical groups in the molecule studied ( local) ( neighbour) ( solvent) ( local) d p (local) > 0, if d > p (local) < 0, if d < p Diamagnetic contribution Paramagnetic contribution Neighbouring group contributions The increasing value of δ (that is, the decrease in shielding) is consistent with the electron withdrawing power of the O atom: it reduces the electron density of the OH proton most, and that proton is strongly deshielded. It reduces the electron density of the distant methyl protons least, and those nuclei are least deshielded. The determination of the area under an absorption line is referred to as the integration of the signal (just as any area under a curve may be determined by mathematical integration). Spectrometers can integrate the absorption automatically. In ethanol the group intensities are in the ratio 3:2:1 because there are three CH 3 protons, two CH 2 protons, and one OH proton in each molecule.

12 The shielding and deshielding effects of the ring current induced in the benzene ring by the applied field. Protons attached to the ring are deshielded but a proton attached to a substituent that projects above the ring is shielded. The solvent contribution An aromatic solvent (benzene here) can give rise to local currents that shield or deshield a proton in a solvent molecule. In this relative orientation of the solvent and solute, the proton on the solute molecule is shielded. The fine structure The splitting of resonances into individual lines is called the fine structure of the spectrum. It arises because of the coupling between spins of different nuclei. This spin spin coupling arises because each magnetic nucleus may contribute to the local field experienced by the other nuclei and so modify their resonance frequencies. The origin of spin spin coupling The electron and nucleus interact: Fermi contact interaction: The 1s electron 1s can penetrate the field resulting from the rotating charge of nucleous and the spherical average of the field it experiences is not zero. Hence the spin of the electron 1s prefer to be antiparallel to the magnetic field of the proton.

13 Two magnetic nuclei interact though the electrons: According to Pauli s principle, two electrons must have antiparallel spins in a bond, hence the two nuclear spins for X and Y are linked to each other via the bonding electrons: that is the polarization mechanism for spin spin coupling. The two arrangements have slightly different energies. Lower energy corresponds to the case when when the nuclear spins are antiparallel. Example: H H, 13C 1H, F H, P H... Two protons interact via an intermediate nucleus (non magnetic): The spin information is transmitted from one bond to the next by a version of the mechanism that accounts for the lower energy of electrons with parallel spins in different atomic orbitals: Hund's rule of maximum multiplicity. In this case, lower energy corresponds to the case when the nuclear spins are parallel. Example: 1H 12C 1H IMPACT ON MEDICINE: Magnetic resonance imaging If an object containing hydrogen nuclei (a tube of water or a human body) is placed in an NMR spectrometer and exposed to a homogeneous magnetic field B 0, then a single resonance signal will be detected with a frequency Consider a magnetic field that varies linearly in the z direction, B = B 0 + Gz. Then the resonant frequencies are All the protons within a given slice (that is, at a given field value) come into resonance and give a signal of the corresponding intensity. B = B 0 + Gz Changing the orientation of the field shows the shape along the corresponding direction, and computer manipulation can be used to build up the three dimensional shape of the sample.

14 Magnetic resonance imaging X rays are known to be dangerous on account of the ionization they cause; The MRI technique is considered safe. The special advantage of MRI is that it can image soft tissues, whereas X rays are largely used for imaging hard, bony structures and abnormally dense regions, such as tumours.

By submitting this essay, I attest that it is my own work, completed in accordance with University regulations. Andrew Yang

By submitting this essay, I attest that it is my own work, completed in accordance with University regulations. Andrew Yang CHEM 251L: Inorganic Chemistry Laboratory Professor Jonathan Parr By submitting this essay, I attest that it is my own work, completed in accordance with University regulations. Andrew Yang An Introduction

More information

Used to determine relative location of atoms within a molecule Most helpful spectroscopic technique in organic chemistry Related to MRI in medicine

Used to determine relative location of atoms within a molecule Most helpful spectroscopic technique in organic chemistry Related to MRI in medicine Structure Determination: Nuclear Magnetic Resonance CHEM 241 UNIT 5C 1 The Use of NMR Spectroscopy Used to determine relative location of atoms within a molecule Most helpful spectroscopic technique in

More information

Proton Nuclear Magnetic Resonance Spectroscopy

Proton Nuclear Magnetic Resonance Spectroscopy Proton Nuclear Magnetic Resonance Spectroscopy Introduction: The NMR Spectrum serves as a great resource in determining the structure of an organic compound by revealing the hydrogen and carbon skeleton.

More information

NMR Spectroscopy. Introduction

NMR Spectroscopy. Introduction Introduction NMR Spectroscopy Over the past fifty years nuclear magnetic resonance spectroscopy, commonly referred to as nmr, has become the most important technique for determining the structure of organic

More information

Nuclear Magnetic Resonance Spectroscopy

Nuclear Magnetic Resonance Spectroscopy Nuclear Magnetic Resonance Spectroscopy Introduction NMR is the most powerful tool available for organic structure determination. It is used to study a wide variety of nuclei: 1 H 13 C 15 N 19 F 31 P 2

More information

Chapter 16: NMR Spectroscopy (i.e., the most exciting thing on the planet)

Chapter 16: NMR Spectroscopy (i.e., the most exciting thing on the planet) Chapter 16: NMR Spectroscopy (i.e., the most exciting thing on the planet) ne day (soon), the following will make a lot of sense to you: 16.1-16.3 The Proton: An Unexpected Journey NMR: Like electrons,

More information

Nuclear Magnetic Resonance Spectroscopy

Nuclear Magnetic Resonance Spectroscopy Nuclear Magnetic Resonance Spectroscopy Nuclear magnetic resonance spectroscopy is a powerful analytical technique used to characterize organic molecules by identifying carbonhydrogen frameworks within

More information

Proton Nuclear Magnetic Resonance ( 1 H-NMR) Spectroscopy

Proton Nuclear Magnetic Resonance ( 1 H-NMR) Spectroscopy Proton Nuclear Magnetic Resonance ( 1 H-NMR) Spectroscopy Theory behind NMR: In the late 1940 s, physical chemists originally developed NMR spectroscopy to study different properties of atomic nuclei,

More information

NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY

NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY NMR Spectroscopy F34 1 NULEAR MAGNETI RESONANE SPETROSOPY Involves interaction of materials with the low-energy radiowave region of the electromagnetic spectrum Origin of Spectra Theory All nuclei possess

More information

Nuclear Magnetic Resonance

Nuclear Magnetic Resonance Nuclear Magnetic Resonance NMR is probably the most useful and powerful technique for identifying and characterizing organic compounds. Felix Bloch and Edward Mills Purcell were awarded the 1952 Nobel

More information

Chapter 13 Spectroscopy NMR, IR, MS, UV-Vis

Chapter 13 Spectroscopy NMR, IR, MS, UV-Vis Chapter 13 Spectroscopy NMR, IR, MS, UV-Vis Main points of the chapter 1. Hydrogen Nuclear Magnetic Resonance a. Splitting or coupling (what s next to what) b. Chemical shifts (what type is it) c. Integration

More information

By far the most important and useful technique to identify organic molecules. Often the only technique necessary.

By far the most important and useful technique to identify organic molecules. Often the only technique necessary. Chapter 13: NMR Spectroscopy 39 NMR Spectroscopy By far the most important and useful technique to identify organic molecules. Often the only technique necessary. NMR spectrum can be recorded for many

More information

13C NMR Spectroscopy

13C NMR Spectroscopy 13 C NMR Spectroscopy Introduction Nuclear magnetic resonance spectroscopy (NMR) is the most powerful tool available for structural determination. A nucleus with an odd number of protons, an odd number

More information

PROTON NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY (H-NMR)

PROTON NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY (H-NMR) PROTON NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY (H-NMR) WHAT IS H-NMR SPECTROSCOPY? References: Bruice 14.1, 14.2 Introduction NMR or nuclear magnetic resonance spectroscopy is a technique used to determine

More information

SIGNAL SPLITTING: Why are there so many peaks all in one area? This is called signal splitting. Example: (image from Illustrated Glossary, splitting)

SIGNAL SPLITTING: Why are there so many peaks all in one area? This is called signal splitting. Example: (image from Illustrated Glossary, splitting) Proton NMR Spectroscopy: Split the signals, not your brain! Before we can understand signal splitting, we have to understand what NMR is. This tutorial will first discuss a few concepts about NMR and then

More information

NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY

NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY PRINCIPLE AND APPLICATION IN STRUCTURE ELUCIDATION Professor S. SANKARARAMAN Department of Chemistry Indian Institute of Technology Madras Chennai 600 036 sanka@iitm.ac.in

More information

Shielding and Chemical Shift. Figure 14.3

Shielding and Chemical Shift. Figure 14.3 Shielding and Chemical Shift Figure 14.3 1 Summary of Shielding Figure 14.4 2 Shielding and Signal Position 3 Characteristic Chemical Shifts Protons in a given environment absorb in a predictable region

More information

Organic Chemistry Tenth Edition

Organic Chemistry Tenth Edition Organic Chemistry Tenth Edition T. W. Graham Solomons Craig B. Fryhle Welcome to CHM 22 Organic Chemisty II Chapters 2 (IR), 9, 3-20. Chapter 2 and Chapter 9 Spectroscopy (interaction of molecule with

More information

Nuclear Shielding and 1. H Chemical Shifts. 1 H NMR Spectroscopy Nuclear Magnetic Resonance

Nuclear Shielding and 1. H Chemical Shifts. 1 H NMR Spectroscopy Nuclear Magnetic Resonance NMR Spectroscopy Nuclear Magnetic Resonance Nuclear Shielding and hemical Shifts What do we mean by "shielding?" What do we mean by "chemical shift?" The electrons surrounding a nucleus affect the effective

More information

Chapter 11 Structure Determination: Nuclear Magnetic Resonance Spectroscopy. Nuclear Magnetic Resonance Spectroscopy. 11.1 Nuclear Magnetic Resonance

Chapter 11 Structure Determination: Nuclear Magnetic Resonance Spectroscopy. Nuclear Magnetic Resonance Spectroscopy. 11.1 Nuclear Magnetic Resonance John E. McMurry http://www.cengage.com/chemistry/mcmurry Chapter 11 Structure Determination: Nuclear Magnetic Resonance Spectroscopy 11.1 Nuclear Magnetic Resonance Spectroscopy Many atomic nuclei behave

More information

Chapter 13 Nuclear Magnetic Resonance Spectroscopy

Chapter 13 Nuclear Magnetic Resonance Spectroscopy Organic Chemistry, 6 th Edition L. G. Wade, Jr. Chapter 13 Nuclear Magnetic Resonance Spectroscopy Jo Blackburn Richland College, Dallas, TX Dallas County Community College District 2006, Prentice Hall

More information

Chapter 15 NMR Spectroscopy

Chapter 15 NMR Spectroscopy Chempocalypse Now! Chapter 15 NMR Spectroscopy Page 1 Chapter 15 NMR Spectroscopy Parts of Topics A5 and A9 from the IB HL Chemistry Curriculum A5 A.5.1 Nuclear magnetic resonance (NMR) spectrometry (2

More information

NMR - Basic principles

NMR - Basic principles NMR - Basic principles Subatomic particles like electrons, protons and neutrons are associated with spin - a fundamental property like charge or mass. In the case of nuclei with even number of protons

More information

Nuclear Magnetic Resonance Spectroscopy

Nuclear Magnetic Resonance Spectroscopy Chapter 8 Nuclear Magnetic Resonance Spectroscopy http://www.yteach.co.uk/page.php/resources/view_all?id=nuclear_magnetic _resonance_nmr_spectroscopy_spin_spectrometer_spectrum_proton_t_pag e_5&from=search

More information

4. It is possible to excite, or flip the nuclear magnetic vector from the α-state to the β-state by bridging the energy gap between the two. This is a

4. It is possible to excite, or flip the nuclear magnetic vector from the α-state to the β-state by bridging the energy gap between the two. This is a BASIC PRINCIPLES INTRODUCTION TO NUCLEAR MAGNETIC RESONANCE (NMR) 1. The nuclei of certain atoms with odd atomic number, and/or odd mass behave as spinning charges. The nucleus is the center of positive

More information

Nuclear Magnetic Resonance (NMR) Wade Textbook

Nuclear Magnetic Resonance (NMR) Wade Textbook Nuclear Magnetic Resonance (NMR) Wade Textbook Background Is a nondestructive structural analysis technique Has the same theoretical basis as magnetic resonance imaging (MRI) Referring to MRI as nuclear

More information

Biophysical Chemistry: NMR Spectroscopy

Biophysical Chemistry: NMR Spectroscopy General Principle The Chemical Shift Vrije Universiteit Brussel 28th October 2011 General Principle Outline 1 General Principle Influence of Electron Clouds 2 3 Outline General Principle Influence of Electron

More information

NMR is the most powerful structure determination tool available to organic chemists.

NMR is the most powerful structure determination tool available to organic chemists. Nuclear Magnetic esonance (NM) Spectrometry NM is the most powerful structure determination tool available to organic chemists. An NM spectrum provides information about: 1. The number of atoms of a given

More information

Background A nucleus with an odd atomic number or an odd mass number has a nuclear spin that can be observed by NMR spectrometers.

Background A nucleus with an odd atomic number or an odd mass number has a nuclear spin that can be observed by NMR spectrometers. NMR Spectroscopy I Reading: Wade chapter, sections -- -7 Study Problems: -, -7 Key oncepts and Skills: Given an structure, determine which protons are equivalent and which are nonequivalent, predict the

More information

H NMR (proton NMR): determines number and type of H atoms 13. C NMR (proton NMR): determines number and type of C atoms

H NMR (proton NMR): determines number and type of H atoms 13. C NMR (proton NMR): determines number and type of C atoms 14.1 An Introduction to NMR Spectroscopy A. The Basics of Nuclear Magnetic Resonance (NMR) Spectroscopy nuclei with odd atomic number have a S = ½ with two spin states (+1/2 and -1/2) 1 H NMR (proton NMR):

More information

NMR SPECTROSCOPY A N I N T R O D U C T I O N T O... Self-study booklet NUCLEAR MAGNETIC RESONANCE. 4 3 2 1 0 δ PUBLISHING

NMR SPECTROSCOPY A N I N T R O D U C T I O N T O... Self-study booklet NUCLEAR MAGNETIC RESONANCE. 4 3 2 1 0 δ PUBLISHING A N I N T R O D U T I O N T O... NMR SPETROSOPY NULEAR MAGNETI RESONANE 4 3 1 0 δ Self-study booklet PUBLISING NMR Spectroscopy NULEAR MAGNETI RESONANE SPETROSOPY Origin of Spectra Theory All nuclei possess

More information

NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY

NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY PRINCIPLE AND APPLICATION IN STRUCTURE ELUCIDATION Professor S. SANKARARAMAN Department of Chemistry Indian Institute of Technology Madras Chennai 600 036 sanka@iitm.ac.in

More information

Proton Nuclear Magnetic Resonance Spectroscopy

Proton Nuclear Magnetic Resonance Spectroscopy CHEM 334L Organic Chemistry Laboratory Revision 2.0 Proton Nuclear Magnetic Resonance Spectroscopy In this laboratory exercise we will learn how to use the Chemistry Department's Nuclear Magnetic Resonance

More information

What is NMR? Innovation with Integrity. Nuclear Magnetic Resonance NMR

What is NMR? Innovation with Integrity. Nuclear Magnetic Resonance NMR What is NMR? Nuclear Magnetic Resonance Innovation with Integrity NMR Nuclear Magnetic Resonance You may have heard the term NMR nuclear magnetic resonance but how much do you actually know about it? NMR

More information

Nuclear Magnetic Resonance (NMR) Spectroscopy cont... Recommended Reading:

Nuclear Magnetic Resonance (NMR) Spectroscopy cont... Recommended Reading: Applied Spectroscopy Nuclear Magnetic Resonance (NMR) Spectroscopy cont... Recommended Reading: Banwell and McCash Chapter 7 Skoog, Holler Nieman Chapter 19 Atkins, Chapter 18 Relaxation processes We need

More information

Signal Manipulation. time domain NMR signal in MHz range is converted to khz (audio) range by mixing with the reference ( carrier ) frequency

Signal Manipulation. time domain NMR signal in MHz range is converted to khz (audio) range by mixing with the reference ( carrier ) frequency NMR Spectroscopy: 3 Signal Manipulation time domain NMR signal in MHz range is converted to khz (audio) range by mixing with the reference ( carrier ) frequency Ref in (MHz) mixer Signal in (MHz) Signal

More information

NMR SPECTROSCOPY. Basic Principles, Concepts, and Applications in Chemistry. Harald Günther University of Siegen, Siegen, Germany.

NMR SPECTROSCOPY. Basic Principles, Concepts, and Applications in Chemistry. Harald Günther University of Siegen, Siegen, Germany. NMR SPECTROSCOPY Basic Principles, Concepts, and Applications in Chemistry Harald Günther University of Siegen, Siegen, Germany Second Edition Translated by Harald Günther JOHN WILEY & SONS Chichester

More information

Introduction to Nuclear Magnetic Resonance Spectroscopy

Introduction to Nuclear Magnetic Resonance Spectroscopy Introduction to Nuclear Magnetic Resonance Spectroscopy Dr. Dean L. Olson, NMR Lab Director School of Chemical Sciences University of Illinois Called figures, equations, and tables are from Principles

More information

The Four Questions to Ask While Interpreting Spectra. 1. How many different environments are there?

The Four Questions to Ask While Interpreting Spectra. 1. How many different environments are there? 1 H NMR Spectroscopy (#1c) The technique of 1 H NMR spectroscopy is central to organic chemistry and other fields involving analysis of organic chemicals, such as forensics and environmental science. It

More information

Determination of Molecular Structure by MOLECULAR SPECTROSCOPY

Determination of Molecular Structure by MOLECULAR SPECTROSCOPY Determination of Molecular Structure by MOLEULAR SPETROSOPY hemistry 3 B.Z. Shakhashiri Fall 29 Much of what we know about molecular structure has been learned by observing and analyzing how electromagnetic

More information

Instrumental Lab. Nuclear Magnetic Resonance. Dr Alex J. Roche

Instrumental Lab. Nuclear Magnetic Resonance. Dr Alex J. Roche Instrumental Lab Nuclear Magnetic Resonance Dr Alex J. Roche 1 Nuclear Magnetic Resonance (NMR) Spectroscopy NMR is the most powerful analytical tool currently available to an organic chemist. NMR allows

More information

The Hydrogen Atom Is a Magnet. http://www.seed.slb.com/en/scictr/watch/gashydrates/detecting.htm

The Hydrogen Atom Is a Magnet. http://www.seed.slb.com/en/scictr/watch/gashydrates/detecting.htm The Hydrogen Atom Is a Magnet Nuclear Magnetic Resonance Spectroscopy (NMR) Proton NMR A hydrogen nucleus can be viewed as a proton, which can be viewed as a spinning charge. As with any spinning charge,

More information

CHEM1002 Worksheet 4: Spectroscopy Workshop (1)

CHEM1002 Worksheet 4: Spectroscopy Workshop (1) CHEM1002 Worksheet 4: Spectroscopy Workshop (1) This worksheet forms part of the Spectroscopy Problem Solving Assignment which represents 10% of the assessment of this unit. You should use the support

More information

For example: (Example is from page 50 of the Thinkbook)

For example: (Example is from page 50 of the Thinkbook) SOLVING COMBINED SPECTROSCOPY PROBLEMS: Lecture Supplement: page 50-53 in Thinkbook CFQ s and PP s: page 216 241 in Thinkbook Introduction: The structure of an unknown molecule can be determined using

More information

C NMR Spectroscopy C NMR. C Transition Energy

C NMR Spectroscopy C NMR. C Transition Energy NMR NMR Spectroscopy is the most abundant natural isotope of carbon, but has a nuclear spin I = 0, rendering it unobservable by NMR. Limited to the observation of the nucleus which constitutes only.% of

More information

Organic Chemistry Nuclear Magnetic Resonance H. D. Roth. Chemistry 307 Chapter 13 Nuclear Magnetic Resonance

Organic Chemistry Nuclear Magnetic Resonance H. D. Roth. Chemistry 307 Chapter 13 Nuclear Magnetic Resonance Chemistry 307 Chapter 13 Nuclear Magnetic Resonance Nuclear magnetic resonance (NMR) spectroscopy is one of three spectroscopic techniques that are useful tools for determining the structures of organic

More information

Structure Determination by NMR

Structure Determination by NMR Structure Determination by NMR * Introduction to NMR * 2D NMR, resonance assignments J Correlated Based Experiments * COSY - Correlated Spectroscopy * NOESY - Nuclear Overhauser Effect Spectroscopy * HETCOR

More information

Nuclear Magnetic Resonance notes

Nuclear Magnetic Resonance notes Reminder: These notes are meant to supplement, not replace, the laboratory manual. Nuclear Magnetic Resonance notes Nuclear Magnetic Resonance (NMR) is a spectrometric technique which provides information

More information

Now that we know why we re putting ourselves through the hassle of understanding all of this, let s get started with the analysis process.

Now that we know why we re putting ourselves through the hassle of understanding all of this, let s get started with the analysis process. 13 C -NMR: Cracking Those Carbons A little background: Protons, neutrons, and electrons all have something called spin. This doesn t mean that they re actually spinning around in tight circles like Olympian

More information

1 H NMR and 13 C NMR spectra interpretation

1 H NMR and 13 C NMR spectra interpretation 1 NMR and 13 C NMR spectra interpretation Ewa Dudziak Introduction Nuclear Magnetic Resonance (NMR) spectroscopy is a powerful method for organic molecule structure determination. Moreover, NMR allows

More information

Trans Fats. What is a trans fat? Trans fatty acids, or trans fats as they are known, are certain

Trans Fats. What is a trans fat? Trans fatty acids, or trans fats as they are known, are certain Trans Fats What is a trans fat? Trans fatty acids, or trans fats as they are known, are certain fats found in such foodstuffs as vegetable shortenings, margarines, crackers, candies baked goods and many

More information

Introduction to 1D and 2D NMR Spectroscopy (1) Basics

Introduction to 1D and 2D NMR Spectroscopy (1) Basics Introduction to 1D and 2D NMR Spectroscopy (1) Basics Lecturer: Weiguo Hu A328 Conte (7-1428) weiguoh@polysci.umass.edu October 2009 1 Content At a Glance Introduction to 1D and 2D NMR Spectroscopy Experimentation

More information

Chemical shift = observed chemical shift in MHz/ frequency of spectrometer (MHz)

Chemical shift = observed chemical shift in MHz/ frequency of spectrometer (MHz) Chapter 4. Physical Basis of NMR Spectroscopy. Today the most widely used method for determining the structure of organic compounds is nuclear magnetic resonance (NMR) spectroscopy. NMR spectroscopy involves

More information

(3)

(3) 1. Organic compounds are often identified by using more than one analytical technique. Some of these techniques were used to identify the compounds in the following reactions. C 3 H 7 Br C 3 H 8 O C 3

More information

Solving Spectroscopy Problems

Solving Spectroscopy Problems Solving Spectroscopy Problems The following is a detailed summary on how to solve spectroscopy problems, key terms are highlighted in bold and the definitions are from the illustrated glossary on Dr. Hardinger

More information

Chemistry 307 Chapter 10 Nuclear Magnetic Resonance

Chemistry 307 Chapter 10 Nuclear Magnetic Resonance Chemistry 307 Chapter 10 Nuclear Magnetic Resonance Nuclear magnetic resonance (NMR) spectroscopy is one of three spectroscopic techniques that are useful tools for determining the structures of organic

More information

ATP. 1941, Fritz Lipmann & Herman Kalckar - ATP role in metabolism. ATP: structure. adenosine triphosphate

ATP. 1941, Fritz Lipmann & Herman Kalckar - ATP role in metabolism. ATP: structure. adenosine triphosphate ATP Living systems need energy to do (i) mechanical work (muscles, cellular motion) (ii) transport of molecules and ions (ion channels) (iii) synthesis of macromolecules (DNA, proteins) Energy must come

More information

Introduction to NMR Spectroscopy and Imaging Assignment for Chapter 02: Chemical shift and J Coupling

Introduction to NMR Spectroscopy and Imaging Assignment for Chapter 02: Chemical shift and J Coupling Introduction to NMR Spectroscopy and Imaging Assignment for Chapter 02: Chemical shift and J Coupling 0. Choose the correct one(s) from the following statements or explain briefly your supporting reason

More information

Department of Chemistry College of Science Sultan Qaboos University. Topics and Learning Outcomes

Department of Chemistry College of Science Sultan Qaboos University. Topics and Learning Outcomes Department of Chemistry College of Science Sultan Qaboos University Title : CHEM 3326 (Applied Spectroscopy) Credits : 3 Course Format : 2 lectures and 2 tutorials Course Text : Spectrometric Identification

More information

NMR Phenomenon. Nuclear Magnetic Resonance. µ A spinning charged particle generates a magnetic field.

NMR Phenomenon. Nuclear Magnetic Resonance. µ A spinning charged particle generates a magnetic field. NMR Phenomenon Nuclear Magnetic Resonance µ A spinning charged particle generates a magnetic field. A nucleus with a spin angular momentum will generate a magnetic moment (μ). If these tiny magnets are

More information

Christ Church 3 rd Year: Magnetic Resonance. Reading. Topics

Christ Church 3 rd Year: Magnetic Resonance. Reading. Topics Christ Church 3 rd Year: Magnetic Resonance Reading The following sources are recommended for this tutorial: Nuclear Magnetic Resonance by P. J. Hore (Oxford Chemistry Primers). This text contains the

More information

CHAPTER 12 INFRARED SPECTROSCOPY. and MASS SPECTROSCOPY

CHAPTER 12 INFRARED SPECTROSCOPY. and MASS SPECTROSCOPY KOT 222 ORGANIC CHEMISTRY II CHAPTER 12 INFRARED SPECTROSCOPY and MASS SPECTROSCOPY Part I Infrared Spectroscopy What is Spectroscopy? Spectroscopy is the study of the interaction of matter and electromagnetic

More information

Prof.M.Perucca CORSO DI APPROFONDIMENTO DI FISICA ATOMICA: (III-INCONTRO) RISONANZA MAGNETICA NUCLEARE

Prof.M.Perucca CORSO DI APPROFONDIMENTO DI FISICA ATOMICA: (III-INCONTRO) RISONANZA MAGNETICA NUCLEARE Prof.M.Perucca CORSO DI APPROFONDIMENTO DI FISICA ATOMICA: (III-INCONTRO) RISONANZA MAGNETICA NUCLEARE SUMMARY (I/II) Angular momentum and the spinning gyroscope stationary state equation Magnetic dipole

More information

Nuclear Magnetic Resonance Lisa M. Larrimore

Nuclear Magnetic Resonance Lisa M. Larrimore Lisa M. The fundamentals of nuclear magnetic resonance (NMR) spectroscopy were explored on samples containing large numbers of protons. Mineral oil and dilluted solutions of CuSO 4 were placed in a permanent

More information

SPECTROSCOPY. NUCLEAR MAGNETIC RESONANCE (NMR) AND INFRARED (IR)

SPECTROSCOPY. NUCLEAR MAGNETIC RESONANCE (NMR) AND INFRARED (IR) EXPERIMENT 9 SPETRSPY. NULEAR MAGNETI RESNANE (NMR) AND INFRARED (IR) Materials Needed approx 100 mg of an ester synthesized in Expt #7 - (octyl acetate, benzyl acetate, or isopentyl acetate) approx 1

More information

NUCLEAR MAGNETIC RESONANCE AND INTRODUCTION TO MASS SPECTROMETRY

NUCLEAR MAGNETIC RESONANCE AND INTRODUCTION TO MASS SPECTROMETRY NUCLEAR MAGNETIC RESNANCE AND INTRDUCTIN T MASS SPECTRMETRY A STUDENT SHULD BE ABLE T: 1. Identify and explain the processes involved in proton and carbon-13 nuclear magnetic resonance (NMR), and mass

More information

Analytical chemistry year 12

Analytical chemistry year 12 Analytical chemistry year 12 1) Consider the molecule on the right. a) How many sets of peaks are present in the 1 H NMR spectrum? 3 b) How many sets of peaks are present in the 13 C NMR spectrum? 4 c)

More information

Determination of Equilibrium Constants using NMR Spectrscopy

Determination of Equilibrium Constants using NMR Spectrscopy CHEM 331L Physical Chemistry Laboratory Revision 2.0 Determination of Equilibrium Constants using NMR Spectrscopy In this laboratory exercise we will measure the Equilibrium Constant K c for the keto-enol

More information

If replacement of each of two hydrogens by some group leads to enantiomers, those hydrogens are enantiotopic

If replacement of each of two hydrogens by some group leads to enantiomers, those hydrogens are enantiotopic Homotopic Hydrogens Hydrogens are chemically equivalent or homotopic if replacing each one in turn by the same group would lead to an identical compound If replacement of each of two hydrogens by some

More information

Determining the Structure of an Organic Compound

Determining the Structure of an Organic Compound Determining the Structure of an Organic Compound The analysis of the outcome of a reaction requires that we know the full structure of the products as well as the reactants In the 19 th and early 20 th

More information

Introductory to NMR Spectroscopy

Introductory to NMR Spectroscopy References: Introductory to NMR Spectroscopy Instructor: Tai-huang Huang ( ) Tel. (886)-2-2652-3036; E. mail: bmthh@ibms.sinica.edu.tw Web site: www.nmr.ibms.sinica.edu.tw/~thh/biophysics/nmr-2.ppt 1.

More information

NMR Spectroscopy of Aromatic Compounds (#1e)

NMR Spectroscopy of Aromatic Compounds (#1e) NMR Spectroscopy of Aromatic Compounds (#1e) 1 H NMR Spectroscopy of Aromatic Compounds Erich Hückel s study of aromaticity in the 1930s produced a set of rules for determining whether a compound is aromatic.

More information

Chemical Shift (δ) 0 (by definition) 0.8-1.0 1.2-1.4 1.4-1.7 1.6-2.6 2.0-3.0 2.2-2.5 2.3-2.8 0.5-6.0 3.4-4.0 3.3-4.0 0.5-5.0

Chemical Shift (δ) 0 (by definition) 0.8-1.0 1.2-1.4 1.4-1.7 1.6-2.6 2.0-3.0 2.2-2.5 2.3-2.8 0.5-6.0 3.4-4.0 3.3-4.0 0.5-5.0 Chemical Shifts 1 H-NMR Type of Hydrogen (CH 3 ) 4 Si RCH 3 RCH 2 R R 3 CH R 2 C=CRCHR 2 RC CH ArCH 3 ArCH 2 R ROH RCH 2 OH RCH 2 OR R 2 NH O RCCH 3 O RCCH 2 R Chemical Shift (δ) 0 (by definition) 0.8-1.0

More information

Determination of Equilibrium Constants using NMR Spectrscopy

Determination of Equilibrium Constants using NMR Spectrscopy CHEM 331L Physical Chemistry Laboratory Revision 1.0 Determination of Equilibrium Constants using NMR Spectrscopy In this laboratory exercise we will measure a chemical equilibrium constant using key proton

More information

Infrared Spectroscopy and Mass Spectrometry

Infrared Spectroscopy and Mass Spectrometry Infrared Spectroscopy and Mass Spectrometry Introduction It is fundamental for an organic chemist to be able to identify, or characterize, the new compound that he/she has just made. Sometimes this can

More information

A 13 C-NMR spectrum. RF Frequency The intensity of the peak doesn t does not necessarily correlate to the number of carbons.

A 13 C-NMR spectrum. RF Frequency The intensity of the peak doesn t does not necessarily correlate to the number of carbons. 13 -NMR We can examine the nuclear magnetic properties of carbon atoms in a molecule to learn about a molecules structure. Most carbons are 12 ; 12 has an even number of protons and neutrons and cannot

More information

Chapter 19 Nuclear Magnetic Resonance Spectroscopy (NMR)

Chapter 19 Nuclear Magnetic Resonance Spectroscopy (NMR) Chapter 19 Nuclear Magnetic Resonance Spectroscopy (NMR) A shorter version of the notes, designed to be covered in 4 days. Problems : 1, 2, 3, 4, 7, 10, 11, 19, 20, 22, 24, 27, 30, 34, 35 Absorption of

More information

1 H and 13 C NMR compared: Both give information about the number of chemically nonequivalent nuclei (nonequivalent

1 H and 13 C NMR compared: Both give information about the number of chemically nonequivalent nuclei (nonequivalent 1 H and 13 C NMR compared: 13 C NMR Spectroscopy Both give information about the number of chemically nonequivalent nuclei (nonequivalent hydrogens or nonequivalent carbons) Both give information about

More information

MRI Physics I: Spins, Excitation, Relaxation

MRI Physics I: Spins, Excitation, Relaxation MRI Physics I: Spins, Excitation, Relaxation Douglas C. Biomedical Engineering University of Michigan Michigan Functional MRI Laboratory Outline Introduction to Nuclear Magnetic Resonance Imaging NMR Spins

More information

2D NMR Spectroscopy. Lecture 3

2D NMR Spectroscopy. Lecture 3 2D NMR Spectroscopy Lecture 3 hemical shifts The chemical environment affects the magnetic field of nuclei. B eff = B o - B loc B eff = B o ( - σ ) σ is the magnetic shielding of the nucleus. Factors that

More information

Introduction to Quantum Mechanics and Multiplet Splitting in 1 H NMR Spectrum: A Demonstration and Classroom Activity

Introduction to Quantum Mechanics and Multiplet Splitting in 1 H NMR Spectrum: A Demonstration and Classroom Activity Introduction to Quantum Mechanics and Multiplet Splitting in 1 H NMR Spectrum: A Demonstration and Classroom Activity John Frost Ph.D. 01/24-2014 Abstract: Quantum mechanics is an incredibly important

More information

Introduction to NMR Part 1. Revised 2/19/07 Anne M. Gorham

Introduction to NMR Part 1. Revised 2/19/07 Anne M. Gorham Introduction to NMR Part 1 Revised 2/19/07 Anne M. Gorham What is an NMR? Niobium-tin-copper clad coil wound like a spool of thread. The current runs through this coil, creating the magnetic field. This

More information

20. NMR Spectroscopy and Magnetic Properties

20. NMR Spectroscopy and Magnetic Properties 20. NMR Spectroscopy and Magnetic Properties Nuclear Magnetic Resonance (NMR) Spectroscopy is a technique used largely by organic, inorganic, and biological chemists to determine a variety of physical

More information

0 10 20 30 40 50 60 70 m/z

0 10 20 30 40 50 60 70 m/z Mass spectrum for the ionization of acetone MS of Acetone + Relative Abundance CH 3 H 3 C O + M 15 (loss of methyl) + O H 3 C CH 3 43 58 0 10 20 30 40 50 60 70 m/z It is difficult to identify the ions

More information

The Experiment Some nuclei have nuclear magnetic moments; just as importantly, some do not

The Experiment Some nuclei have nuclear magnetic moments; just as importantly, some do not Chemistry 2600 Lecture Notes Chapter 15 Nuclear Magnetic Resonance Spectroscopy Page 1 of 23 Structure Determination in Organic Chemistry: NMR Spectroscopy Three main techniques are used to determine the

More information

TYPES OF INFORMATION FROM NMR SPECTRUM

TYPES OF INFORMATION FROM NMR SPECTRUM TYPES OF INFORMATION FROM NMR SPETRUM 1. Each different type of hydrogen gives a peak or group of peaks (multiplet). 2. The chemical shift (δ, in ppm) gives a clue as to the type of hydrogen generating

More information

Nuclear Magnetic Resonance Spectroscopy (NMR)

Nuclear Magnetic Resonance Spectroscopy (NMR) Nuclear Magnetic Resonance Spectroscopy (NMR) NMR is a spectroscopic technique which relies on the magnetic properties of the atomic nucleus. When placed in a strong magnetic field, certain nuclei resonate

More information

Nuclear Magnetic Resonance Spectroscopy

Nuclear Magnetic Resonance Spectroscopy Most spinning nuclei behave like magnets. Nuclear Magnetic Resonance Spectroscopy asics owever, as opposed to the behavior of a classical magnet the nuclear spin magnetic moment does not always align with

More information

CHE334 Identification of an Unknown Compound By NMR/IR/MS

CHE334 Identification of an Unknown Compound By NMR/IR/MS CHE334 Identification of an Unknown Compound By NMR/IR/MS Purpose The object of this experiment is to determine the structure of an unknown compound using IR, 1 H-NMR, 13 C-NMR and Mass spectroscopy. Infrared

More information

How lasers work. The laser medium. Population Inversion. L 36 Modern Physics [2] Spontaneous vs Stimulated Emission.

How lasers work. The laser medium. Population Inversion. L 36 Modern Physics [2] Spontaneous vs Stimulated Emission. L 36 Modern Physics [2] How lasers work Medical applications of lasers Applications of high power lasers Medical imaging techniques CAT scans MRI s How lasers work First we must understand the difference

More information

Introduction to Nuclear Magnetic Resonance (NMR) And. NMR Metabolomics

Introduction to Nuclear Magnetic Resonance (NMR) And. NMR Metabolomics Introduction to Nuclear Magnetic Resonance (NMR) And NMR Metabolomics Acknowledgment: Some slides from talks by Natalia Serkova, Wimal Pathmasiri, and from many internet sources (e.g., U of Oxford, Florida

More information

Pulsed Nuclear Magnetic Resonance Analysis of Glycerin and Mineral Oil

Pulsed Nuclear Magnetic Resonance Analysis of Glycerin and Mineral Oil Pulsed Nuclear Magnetic Resonance Analysis of Glycerin and Mineral Oil Janet Chao, Dean Henze, Patrick Smith, Kent Lee February 27, 2013 Abstract Pulsed nuclear magnetic resonance was used in order to

More information

Chapter 19 Nuclear Magnetic Resonance Spectroscopy (NMR)

Chapter 19 Nuclear Magnetic Resonance Spectroscopy (NMR) Chapter 19 Nuclear Magnetic Resonance Spectroscopy (NMR) 23 pages 2 weeks worth! Problems : 1, 2, 3, 4, 7, 10, 11, 19, 20, 22, 24, 27, 30, 34, 35 Absorption of radio-frequency E from 4-900 MHz (wavelengths

More information

Nuclear Physics. Nuclear Physics comprises the study of:

Nuclear Physics. Nuclear Physics comprises the study of: Nuclear Physics Nuclear Physics comprises the study of: The general properties of nuclei The particles contained in the nucleus The interaction between these particles Radioactivity and nuclear reactions

More information

Infrared Spectroscopy 紅 外 線 光 譜 儀

Infrared Spectroscopy 紅 外 線 光 譜 儀 Infrared Spectroscopy 紅 外 線 光 譜 儀 Introduction Spectroscopy is an analytical technique which helps determine structure. It destroys little or no sample (nondestructive method). The amount of light absorbed

More information

Interpretation of 1 H spectra

Interpretation of 1 H spectra Interpretation of 1 spectra So far we have talked about different NMR techniques and pulse sequences, but we haven t focused seriously on how to analyze the data that we obtain from these experiments.

More information

Spectroscopy. energy Low λ High ν. UV-visible

Spectroscopy. energy Low λ High ν. UV-visible Spectroscopy frequency 10 20 10 18 10 16 10 14 10 12 10 8 Gamma rays X-rays UV IR Microwaves Radiowaves High energy Low λ High ν visible Low energy quantization of energy levels X-Ray UV-visible Infrared

More information

Final Semester 1 Review Sheet

Final Semester 1 Review Sheet Final Semester 1 Review Sheet Chapter 1&3 What is Chemistry Matter Mass Weight Scientific method o Observation Observation vs. inference (know the difference) Qualitative data Quantitative data o Hypothesis

More information

Nuclear Magnetic Resonance and the Measurement of Relaxation Times of Acetone with Gadolinium

Nuclear Magnetic Resonance and the Measurement of Relaxation Times of Acetone with Gadolinium Nuclear Magnetic Resonance and the Measurement of Relaxation Times of Acetone with Gadolinium Xia Lee and Albert Tsai June 15, 2006 1 1 Introduction Nuclear magnetic resonance (NMR) is a spectroscopic

More information