UV-Vis Spectroscopy. Chem 744 Spring Gregory R. Cook, NDSU Thursday, February 14, 13
|
|
- Phebe Merritt
- 6 years ago
- Views:
Transcription
1 UV-Vis Spectroscopy Chem 744 Spring 2013
2 UV-Vis Spectroscopy Every organic molecule absorbs UV-visible light Energy of electronic transitions saturated functionality not in region that is easily accessible (obscured by solvent and atmosphere) Conjugation ultraviolet
3 Basic Instrument Design 3
4 Electronic Transitions possible electronic transitions σ ΔE = [E excited - E ground ] = hν π σ σ alkanes E n σ π π π carbonyls alkenes, carbonyls, alkynes, etc. π n σ heteroatoms -, N, S, X, etc. σ n π carbonyls 4
5 Beer-Lambert Law A = log ( I0 / I1 ) = ε l c A is absorbance (no units) ε is the molar absorptivity or extinction coefficient (L mol -1 cm -1 ) (how strongly it absorbs - intrinsic) l is the path length of the sample (cm) c is the concentration of the comppound (mol L -1 ) I0 is the intensity of the incident light I1 is the intensity of the transmitted light 5
6 rganic Molecules UV-Vis Characteristics Most organic molecules absorb in UV region unless highly conjugated Most common detector for HPLC best to have conjugated chromophore Spectra are broad (why?) making it useful for qualitative identification Can quantitate using Beer s law analysis 6
7 Presentation of Spectra many vibrational bands - many slightly different absorbances Absorption of light occurs in s, faster than vibrational changes Franck-Codon principle - absorption occurs via a vertical transition - all bond lengths, angles, conformations and solvationare conserved in the transition. hyperchromic A hypsochromic (blue) λ max bathochromic (red) hypochromic λ max 200 nm 800 nm 7
8 Presentation of Spectra 8
9 Solvents Measuring UV-Vis spectra <200 nm is impractical Quartz glass cutoff 210 nm fused synthetic silica can get down to 190 nm Solvent Cutoffs solvent cut-off (nm) water 205 acetonitrile 210 cyclohexane 210 diethyl ether 210 ethanol 210 methanol 210 dioxane 220 solvent cut-off (nm) THF 220 dichloromethane 235 chloroform 245 carbon tet 265 benzene 280 acetone 300 9
10 Solvent effects on spectra H 10
11 Selection Rules Not all transitions are observed Depends on symmetry and multiplicity Forbidden Transitions (e.g. n-π*) can be seen but are weak Molecular vibrations can disrupt the symmetry σ π possible electronic transitions E n π σ 11
12 Transitions 12
13 Nature of absorption Ethane - λmax = 135 nm H H H C C H hν H H 13
14 Nature of absorption Acetone - λmax = ~166 nm (n-σ * ; ε = >10000) λmax = 188 nm (π-σ * ; ε = 1860) λmax = 279 nm (n-π * ; ε = 15) 14
15 Tetraphenyldicyclopentadienone 15
16 Ethylene Ethylene π-π * λmax = 165 nm (n-σ * ; ε = 16,000) Substitution with an atom containing non-bonding electrons ( H, R, NH2, NHR, SH, SR, Hal) results in a bathochromic shift > the non-bonding electrons interact with the π-orbitals of the double bond the energy difference between the HM and LUM decreases 16
17 Conjugation 17
18 Conjugation Conjugation of two or more double bonds results in decreasing energy difference between the HM and LUM λ max
19 Conjugation 19
20 Conjugation Woodward-Fieser Rules work well up to 4 double bonds base alkyls 10 exo bond 5 total 232 (actual 237) base alkyls 15 exo bond 5 total 234 (actual 235) for more than 4 conjugated double bonds: Fieser-Kuhn Rules λ max = (# alkyl substituents) + n(48-1.7n) (# endo) - 10(# exo) 20
21 Conjugation Lycopene and beta-carotene λ max = (# alkyl substituents) + n(48-1.7n) (# endo) - 10(# exo) λ max = (8) + 11( ) = 476 nm λ max (actual) = 474 λ max = (10) + 11( ) (2) - 0 = nm λ max (actual) =
22 Benzene 22
23 Aromatic Substituent Effects 23
24 Aromatic Substituent Effects 24
25 Polyaromatic Systems 25
26 Carbonyl Compounds 26
27 Carbonyl Compounds C aldehyde or ketone n -> σ * 166 nm ε = 16,000 π -> π * 189 nm ε = 900 n -> π * 166 nm ε = H H Et NH H 292 Cl H
28 Carbonyl Compounds 28
ULTRAVIOLET SPECTROSCOPY or ELECTRONIC SPECTROSCOPY
ULTRAVILET SPECTRSCPY or ELECTRNIC SPECTRSCPY S. SANKARARAMAN Department of Chemistry Indian Institute of Technology Madras Chennai 600036, INDIA Sanka@iitm.ac.in Absorption of electromagnetic radiation
More informationUltraviolet Spectroscopy. CH- 521 Course on Interpreta2ve Molecular Spectroscopy; Course Instructor: Krishna P. Kaliappan
Ultraviolet Spectroscopy CH- 521 Course on Interpreta2ve Molecular Spectroscopy; Course Instructor: Krishna P. Kaliappan Ultraviolet Spectroscopy UV light can be absorbed by molecules to excite higher
More informationMolecular Spectroscopy
Molecular Spectroscopy Types of transitions: 1) Electronic (UV-Vis-Near IR) 2) Vibrational (IR) 3) Rotational (microwave) Electronic Absorption Spectra π π* Gary L. Miessler and Donald A. Tarr, Inorganic
More informationUV Spectroscopy: Empirical Approach to Molecular Structures. Dr. Mishu Singh Department of Chemistry M. P.Govt P. G.
UV Spectroscopy: Empirical Approach to Molecular Structures Dr. Mishu Singh Department of Chemistry M. P.Govt P. G.College, Hardoi WHAT IS SPECTROSCOPY? Atoms and molecules interact with electromagnetic
More informationSpectroscopy may be defined as the study of interaction between electromagnetic radiations and matter.
Spectroscopy may be defined as the study of interaction between electromagnetic radiations and matter. Spectroscopy has a wide range of applications. It is heavily used in astronomy and remote sensing.
More informationSpectroscopy. Page 1 of 8 L.Pillay (2012)
Spectroscopy Electromagnetic radiation is widely used in analytical chemistry. The identification and quantification of samples using electromagnetic radiation (light) is called spectroscopy. Light has
More informationUV / Visible Spectroscopy. Click icon to add picture
UV / Visible Spectroscopy Click icon to add picture Spectroscopy It is the branch of science that deals with the study of interaction of matter with light. OR It is the branch of science that deals with
More informationtwo slits and 5 slits
Electronic Spectroscopy 2015January19 1 1. UV-vis spectrometer 1.1. Grating spectrometer 1.2. Single slit: 1.2.1. I diffracted intensity at relative to un-diffracted beam 1.2.2. I - intensity of light
More information9/28/10. Visible and Ultraviolet Molecular Spectroscopy - (S-H-C Chapters 13-14) Valence Electronic Structure. n σ* transitions
Visible and Ultraviolet Molecular Spectroscopy - (S-H-C Chapters 13-14) Electromagnetic Spectrum - Molecular transitions Widely used in chemistry. Perhaps the most widely used in Biological Chemistry.
More informationElectronic Excitation by UV/Vis Spectroscopy :
Electronic Excitation by UV/Vis Spectroscopy : X-ray: core electron excitation UV: valance electronic excitation IR: molecular vibrations Radio waves: Nuclear spin states (in a magnetic field) The wavelength
More informationUV Visible Spectroscopy
UV Visible Spectroscopy It involves the measurement of absorption of light in the UV region(10-200(far UV)-200-400nm(near UV) and visible region(400-800nm)by the compound under investigation. It is also
More informationElectronic Excitation by UV/Vis Spectroscopy :
Electronic Excitation by UV/Vis Spectroscopy : X-ray: core electron excitation UV: valance electronic excitation IR: molecular vibrations Radio waves: Nuclear spin states (in a magnetic field) The wavelength
More informationMore information can be found in Chapter 12 in your textbook for CHEM 3750/ 3770 and on pages in your laboratory manual.
CHEM 3780 rganic Chemistry II Infrared Spectroscopy and Mass Spectrometry Review More information can be found in Chapter 12 in your textbook for CHEM 3750/ 3770 and on pages 13-28 in your laboratory manual.
More informationSpektroskopi Molekul Organik
Spektroskopi Molekul rganik Chapter 7: UV & electronic transitions Usable ranges & observations Selection rules Band Structure Instrumentation & Spectra Beer-Lambert Law Application of UV-spec 1 Dosen:
More informationTerms used in UV / Visible Spectroscopy
Terms used in UV / Visible Spectroscopy Chromophore The part of a molecule responsible for imparting color, are called as chromospheres. OR The functional groups containing multiple bonds capable of absorbing
More informationAdvanced Analytical Chemistry
84.514 Advanced Analytical Chemistry Part III Molecular Spectroscopy (continued) Website http://faculty.uml.edu/david_ryan/84.514 http://www.cem.msu.edu/~reusch/virtualtext/ Spectrpy/UV-Vis/spectrum.htm
More informationMolecular Spectroscopy. H 2 O e -
Molecular Spectroscopy ν (cm -1 ) λ (cm) 10 6 10 8 10 10 10 12 10 14 10 16 10 18 10 20 10 22 ν (Hz) NMR ESR microwave IR UV/Vis VUV X-Ray Gamma Ray H 2 e - UV/Vis Spectroscopy absorption technique X hν
More informationInfrared Spectroscopy: Identification of Unknown Substances
Infrared Spectroscopy: Identification of Unknown Substances Suppose a white powder is one of the four following molecules. How can they be differentiated? H N N H H H H Na H H H H H A technique that is
More informationFerdowsi University of Mashhad
Spectroscopy in Inorganic Chemistry 2 Diatomic molecule C v and D h HCN H-H 3 contribution orbital electron Σ 0 σ 1 Π 1 π 1 Δ 2 δ 1 Φ 3 δ 1 Σ + Σ - 4 Linear molecule NO 2s+1 2 Π A 1 =Σ + 0 A 2 =Σ - 0 E
More informationApplication of IR Raman Spectroscopy
Application of IR Raman Spectroscopy 3 IR regions Structure and Functional Group Absorption IR Reflection IR Photoacoustic IR IR Emission Micro 10-1 Mid-IR Mid-IR absorption Samples Placed in cell (salt)
More informationQuímica Orgânica I. Ciências Farmacêuticas Bioquímica Química. Análise estrutural AFB QO I 2007/08 1 AFB QO I 2007/08 2
Química Orgânica I Ciências Farmacêuticas Bioquímica Química AFB QO I 2007/08 1 Análise estrutural AFB QO I 2007/08 2 1 Adaptado de: Organic Chemistry, 6th Edition; L. G. Wade, Jr. Organic Chemistry, William
More informationSpectroscopy in Inorganic Chemistry. Electronic Absorption Spectroscopy
Spectroscopy in Inorganic Chemistry Diatomic molecule C v and D h NO H-H 2 contribution orbital Σ 0 σ Π 1 π Δ 2 δ Φ 3 δ 3 Linear molecule NO 2s+1 2 Π A 1 =Σ + 0 A 2 =Σ - 0 E 1 =Π 1 E 2 =Δ 2 E 3 =Φ 3 4
More informationElectronic Excitation by UV/Vis Spectroscopy :
SPECTROSCOPY Light interacting with matter as an analytical tool III Pharm.D Department of Pharmaceutical Analysis SRM College Of Pharmacy,Katankulathur Electronic Excitation by UV/Vis Spectroscopy : X-ray:
More informationWilliam H. Brown & Christopher S. Foote
Requests for permission to make copies of any part of the work should be mailed to:permissions Department, Harcourt Brace & Company, 6277 Sea Harbor Drive, Orlando, Florida 32887-6777 William H. Brown
More informationStructure Determination. How to determine what compound that you have? One way to determine compound is to get an elemental analysis
Structure Determination How to determine what compound that you have? ne way to determine compound is to get an elemental analysis -basically burn the compound to determine %C, %H, %, etc. from these percentages
More informationand Ultraviolet Spectroscopy
Organic Chemistry, 7 th Edition L. G. Wade, Jr. Chapter 15 Conjugated Systems, Orbital Symmetry, and Ultraviolet Spectroscopy 2010, Prentice all Conjugated Systems Conjugated double bonds are separated
More informationPaper: 12, Organic Spectroscopy Module: 5, Applications of UV spectroscopy
Subject Chemistry Paper No and Title Module No and Title Module Tag Paper 12: Organic Spectroscopy Applications of UV-visible Spectroscopy CHE_P12_M5 TABLE OF CONTENTS 1. Learning Outcomes 2. Introduction
More informationConjugated Systems. With conjugated double bonds resonance structures can be drawn
Conjugated Systems Double bonds in conjugation behave differently than isolated double bonds With conjugated double bonds resonance structures can be drawn With isolated double bonds cannot draw resonance
More informationE35 SPECTROSCOPIC TECHNIQUES IN ORGANIC CHEMISTRY
E35 SPECTRSCPIC TECNIQUES IN RGANIC CEMISTRY Introductory Comments. These notes are designed to introduce you to the basic spectroscopic techniques which are used for the determination of the structure
More informationInfrared Spectroscopy
Infrared Spectroscopy Introduction Spectroscopy is an analytical technique which helps determine structure. It destroys little or no sample. The amount of light absorbed by the sample is measured as wavelength
More informationChemistry 304B, Spring 1999 Lecture 5 1. UV Spectroscopy:
Chemistry 304B, Spring 1999 Lecture 5 1 Ultraviolet spectroscopy; UV Spectroscopy: Infrared spectroscopy; Nuclear magnetic resonance spectroscopy General basis of spectroscopy: Shine light at a collection
More informationUltraviolet and Visible Spectroscopy
BSC 3 rd YEAR SUBJECT CHEMISTRY SESSION 2016-2017 ORGANIC PORTION(B) UNIT I Ultraviolet and Visible Spectroscopy ELECTROMAGNETIC RADIATIONS Visible light is a form of energy which can be described by two
More information09/05/40 MOLECULAR ABSORPTION METHODS
MOLECULAR ABSORPTION METHODS Absorption spectroscopy refers to spectroscopic techniques that measure the absorption of radiation, as a function of wavelength ( absorption spectrum ), due to its interaction
More informationTerms used in UV / Visible Spectroscopy
Terms used in UV / Visible Spectroscopy Chromophore The part of a molecule responsible for imparting color, are called as chromospheres. OR The functional groups containing multiple bonds capable of absorbing
More informationAdvanced Pharmaceutical Analysis
Lecture 2 Advanced Pharmaceutical Analysis IR spectroscopy Dr. Baraa Ramzi Infrared Spectroscopy It is a powerful tool for identifying pure organic and inorganic compounds. Every molecular compound has
More informationUV-Vis Absorption Experiment 5: Beer- Lambert Law and the Temperature Dependence of the Crystal Violet- Sodium Hydroxide Reaction
1 UV-Vis Absorption Experiment 5: Beer- Lambert Law and the Temperature Dependence of the Crystal Violet- Sodium Hydroxide Reaction Overview In Part A of this experiment, the absorption behaviour of crystal
More informationIncreasing energy. ( 10 4 cm -1 ) ( 10 2 cm -1 )
The branch of science which deals with the interaction of electromagnetic radiation with matter is called spectroscopy The energy absorbed or emitted in each transition corresponds to a definite frequency
More informationUV-Vis optical fiber assisted spectroscopy in thin films and solutions
UV-Vis optical fiber assisted spectroscopy in thin films and solutions Description UV-Visible absorption and transmission spectra provide fundamental information for all experiments related to the attenuation
More information7a. Structure Elucidation: IR and 13 C-NMR Spectroscopies (text , , 12.10)
2009, Department of Chemistry, The University of Western Ontario 7a.1 7a. Structure Elucidation: IR and 13 C-NMR Spectroscopies (text 11.1 11.5, 12.1 12.5, 12.10) A. Electromagnetic Radiation Energy is
More informationInstrumental Chemical Analysis
L6 page 1 Instrumental Chemical Analysis Ultraviolet and visible spectroscopy Dr. Ahmad Najjar Philadelphia University Faculty of Pharmacy Department of Pharmaceutical Sciences 2 nd semester, 2016/2017
More informationChapter 4 Ultraviolet and visible spectroscopy Molecular Spectrophotometry
Chapter 4 Ultraviolet and visible spectroscopy Molecular Spectrophotometry Properties of light Electromagnetic radiation and electromagnetic spectrum Absorption of light Beer s law Limitation of Beer s
More informationORGANIC - BROWN 8E CH INFRARED SPECTROSCOPY.
!! www.clutchprep.com CONCEPT: PURPOSE OF ANALYTICAL TECHNIQUES Classical Methods (Wet Chemistry): Chemists needed to run dozens of chemical reactions to determine the type of molecules in a compound.
More informationRadiant energy is proportional to its frequency (cycles/s = Hz) as a wave (Amplitude is its height) Different types are classified by frequency or
CHEM 241 UNIT 5: PART B INFRA-RED RED SPECTROSCOPY 1 Spectroscopy of the Electromagnetic Spectrum Radiant energy is proportional to its frequency (cycles/s = Hz) as a wave (Amplitude is its height) Different
More informationTable 8.2 Detailed Table of Characteristic Infrared Absorption Frequencies
Table 8.2 Detailed Table of Characteristic Infrared Absorption Frequencies The hydrogen stretch region (3600 2500 cm 1 ). Absorption in this region is associated with the stretching vibration of hydrogen
More informationCHEM 3760 Orgo I, S12, Exp 5 (Lab #6) (TECH 710: IR Unknown)
CHEM 3760 rgo I, S12, Exp 5 (Lab #6) (TECH 710: IR Unknown) LAB REPRT ISTRUCTIS Identifying an Unknown Compound by Infrared Spectroscopy (IR) Carefully read all instructions and complete Section I on page
More informationInfrared Spectroscopy
Infrared Spectroscopy IR Spectroscopy Used to identify organic compounds IR spectroscopy provides a 100% identification if the spectrum is matched. If not, IR at least provides information about the types
More informationAnalytical Technologies in Biotechnology Prof. Dr. Ashwani K Sharma Department of Biotechnology Indian Institute of Technology, Roorkee
Analytical Technologies in Biotechnology Prof. Dr. Ashwani K Sharma Department of Biotechnology Indian Institute of Technology, Roorkee Module - 6 Spectroscopic Techniques Lecture - 2 UV-Visible Spectroscopy
More informationInstrumental Chemical Analysis
L6 page 1 Instrumental Chemical Analysis Ultraviolet and visible spectroscopy Dr. Ahmad Najjar Philadelphia University Faculty of Pharmacy Department of Pharmaceutical Sciences 2 nd semester, 2016/2017
More informationConjugated Dienes and Ultraviolet Spectroscopy
Conjugated Dienes and Ultraviolet Spectroscopy Key Words Conjugated Diene Resonance Structures Dienophiles Concerted Reaction Pericyclic Reaction Cycloaddition Reaction Bridged Bicyclic Compound Cyclic
More informationLambert s law. Beer s law. di x / I x = -kdx (-di x = k I x dx) = - a c dx. I/I 0 = e -kl T = A = - log (T) = - log (I/I 0 )
di x / I x = -kdx (-di x = k I x dx) Integrating this equation from x=0 ~ l (I x =I 0 ~I) gives ; ln I ln I 0 = -kl ln I/I 0 = -kl Expressing the number of photons absorbed by the slab as di x, and the
More informationConjugated Dienes. Chapter 14 Organic Chemistry, 8 th Edition John E. McMurry
Conjugated Dienes Chapter 14 Organic Chemistry, 8 th Edition John E. McMurry 1 Dienes Propadiene (allene) is a cumulated diene 1,3-Butadiene is a conjugated diene. 1,4-Pentadiene is an isolated diene.
More informationConjugated Dienes. Chapter 14 Organic Chemistry, 8 th Edition John E. McMurry
Conjugated Dienes Chapter 14 Organic Chemistry, 8 th Edition John E. McMurry 1 Dienes Propadiene (allene) is a cumulated diene 1,3-Butadiene is a conjugated diene. 1,4-Pentadiene is an isolated diene.
More informationA very brief history of the study of light
1. Sir Isaac Newton 1672: A very brief history of the study of light Showed that the component colors of the visible portion of white light can be separated through a prism, which acts to bend the light
More information12. Structure Determination: Mass Spectrometry and Infrared Spectroscopy
12. Structure Determination: Mass Spectrometry and Infrared Spectroscopy Determining the Structure of an Organic Compound The analysis of the outcome of a reaction requires that we know the full structure
More informationUltraviolet-Visible Spectroscopy
Ultraviolet-Visible Spectroscopy Introduction to UV-Visible Absorption spectroscopy from 160 nm to 780 nm Measurement of transmittance Conversion to absorbance * A=-logT=εbc Measurement of transmittance
More informationChapter 12 Mass Spectrometry and Infrared Spectroscopy
Organic Chemistry, 6 th Edition L. G. Wade, Jr. Chapter 12 Mass Spectrometry and Infrared Spectroscopy Jo Blackburn Richland College, Dallas, TX Dallas County Community College District 2006, Prentice
More informationLAB #1: ABSORPTION SPECTRA OF CONJUGATED DYES
Chemistry 7 Gustavus Adolphus College LAB #1: ABSORPTIO SPECTRA OF COJUGATED DYES Abstract Ultraviolet-visible spectroscopy is used to explore the electronic structure of several conjugated polyene dyes,
More informationLecture 09 MO theory. (Refer Slide Time: 00:33)
(Refer Slide Time: 00:33) Atomic and Molecular Absorption Spectrometry for Pollution Monitoring Dr. J R Mudakavi Department of Chemical Engineering Indian Institute of Science, Bangalore Lecture 09 MO
More informationMASS and INFRA RED SPECTROSCOPY
MASS and INFRA RED SPECTRSCPY Mass Spectroscopy The mass spectrometer was looked at in Unit 1. It was noted there that compounds produce fragmentation patterns when passes through a mass spectrometer.
More informationChapter 9. Organic Chemistry: The Infinite Variety of Carbon Compounds. Organic Chemistry
Chapter 9 Organic Chemistry: The Infinite Variety of Carbon Compounds Organic Chemistry Organic chemistry is defined as the chemistry of carbon compounds. Of tens of millions of known chemical compounds,
More informationChapter 14: Conjugated Dienes and Ultraviolet Spectroscopy Diene: molecule with two double bonds Conjugated diene: alternating double and single bonds
Chapter 14: Conjugated Dienes and Ultraviolet Spectroscopy Diene: molecule with two double bonds Conjugated diene: alternating double and single bonds C-C single bond lkene Diene C=C double bonds Conjugate
More informationInfrared Spectroscopy An Instrumental Method for Detecting Functional Groups
Infrared Spectroscopy An Instrumental Method for Detecting Functional Groups 1 The Electromagnetic Spectrum Infrared Spectroscopy I. Physics Review Frequency, υ (nu), is the number of wave cycles that
More information4.3A: Electronic transitions
Ashley Robison My Preferences Site Tools Popular pages MindTouch User Guide FAQ Sign Out If you like us, please share us on social media. The latest UCD Hyperlibrary newsletter is now complete, check it
More informationOrganic Chemistry: CHEM2322
Conjugated Systems Organic Chemistry: We met in Chem 2321 unsaturated bonds as either a C=C bond or C C bond. If these unsaturated bonds are well separated then they react independently however if there
More informationCH 3. mirror plane. CH c d
CAPTER 20 Practice Exercises 20.1 The index of hydrogen deficiency is two. The structural possibilities include two double bonds, a double do 20.3 (a) As this is an alkane, it contains only C and and has
More informationLearning Guide for Chapter 3 - Infrared Spectroscopy
Learning Guide for hapter 3 - Infrared Spectroscopy I. Introduction to spectroscopy - p 1 II. Molecular vibrations - p 3 III. Identifying functional groups - p 6 IV. Interpreting an IR spectrum - p 12
More informationMOLECULAR ABSORPTION METHODS
MOLECULAR ABSORPTION METHODS Absorption spectroscopy refers to spectroscopic techniques that measure the absorption of radiation, as a function of wavelength ( absorption spectrum ), due to its interaction
More informationBasics of UV-Visible Spectroscopy *
OpenStax-CNX module: m34525 1 Basics of UV-Visible Spectroscopy * Brittany L. Oliva-Chatelain Andrew R. Barron This work is produced by OpenStax-CNX and licensed under the Creative Commons Attribution
More informationCHAPTER 13 LECTURE NOTES
CHAPTER 13 LECTURE NOTES Spectroscopy is concerned with the measurement of (a) the wavelengths (or frequencies) at which molecules absorb/emit energy, and (b) the amount of radiation absorbed at these
More informationIntroduction. The analysis of the outcome of a reaction requires that we know the full structure of the products as well as the reactants
Introduction The analysis of the outcome of a reaction requires that we know the full structure of the products as well as the reactants Spectroscopy and the Electromagnetic Spectrum Unlike mass spectrometry,
More informationlevels. The signal is either absorbance vibrational and rotational energy levels or percent transmittance of the analyte
1 In this chapter, absorption by molecules, rather than atoms, is considered. Absorption in the ultraviolet and visible regions occurs due to electronic transitions from the ground state to excited state.
More informationC h a p t e r S i x t e e n: Nuclear Magnetic Resonance Spectroscopy. An 1 H NMR FID of ethanol
0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0 2.2 2.4 2.6 2.8 3.0 3.2 3.4 3.6 C h a p t e r S i x t e e n: Nuclear Magnetic Resonance Spectroscopy An 1 NMR FID of ethanol Note: Problems with italicized numbers
More informationFebruary 8, 2018 Chemistry 328N
Lecture 7 UV-Vis spectroscopy February 8, 2018 First Midterm Exam When: Wednesday, 2/14 When: 7-9 PM (please do not be late) Where: WEL 2.122 This room!!! What: Covers material through today s lecture
More information1. Which compound would you expect to have the lowest boiling point? A) NH 2 B) NH 2
MULTIPLE CICE QUESTINS Topic: Intermolecular forces 1. Which compound would you expect to have the lowest boiling point? A) N 2 B) N 2 C) N D) E) N Ans: : N 2 D Topic: Molecular geometry, dipole moment
More informationChapter 5 Materials Characterization Lecture III
Chapter 5 Materials Characterization Lecture III Dr. Alagiriswamy A A (PhD., PDF) Dept. of Physics and Nanotechnology SRM University Main Campus, Ktr., SRM Nagar, Chennai, Tamilnadu 5.0 Characterization
More informationMost organic molecules and functional groups are transparent in the portions of the electromagnetic ULTRAVIOLET SPECTROSCOPY
14782_07_h7_p381-417.pp2.qxd 2/2/08 1:22 AM Page 381 A P T E R 7 ULTRAVILET SPETRSPY Most organic molecules and functional groups are transparent in the portions of the electromagnetic spectrum that we
More informationGeneral Infrared Absorption Ranges of Various Functional Groups
General Infrared Absorption Ranges of Various Functional Groups Frequency Range Bond Type of Compound cm -1 Intensity C Alkanes 2850-2970 Strong 1340-1470 Strong C Alkenes 3010-3095 Medium 675-995 Strong
More informationCHEM 261 Notes Nov 22, 2017 REVIEW:
155 CEM 261 Notes Nov 22, 2017 REVIEW: Recall how we can show the energy levels of the atomic orbitals of C. If the C is sp 2 hybridized, two of the 2p orbitals combine with the 2s orbital to form two
More informationInfrared Spectroscopy
x-rays ultraviolet (UV) visible Infrared (I) microwaves radiowaves near I middle I far I λ (cm) 8 x 10-5 2.5 x 10-4 2.5 x 10-3 2.5 x 10-2 µ 0.8 2.5 25 250 ν (cm -1 ) 13,000 4,000 400 40 ν (cm -1 1 ) =
More informationORGANIC SPECTROSCOPY NOTES
- 1 - ORGANIC SPECTROSCOPY NOTES Basics of Spectroscopy UV/vis, IR and NMR are all types of Absorption Spectroscopy, where EM radiation corresponding to exactly the energy of specific excitations in molecules
More informationUV-Vis spektrometrie. Brno 2016, Dominik Heger, Ústav chemie a RECETOX, MU
UV-Vis spektrometrie Brno 2016, Dominik Heger, http://hegerd.sci.muni.cz/ Ústav chemie a RECETOX, MU Sluneční světlo What is UV-VIS spectroscopy measuring? Electronic transitions. l / nm 185-200 Vacuum-UV
More informationORGANIC - BRUICE 8E CH MASS SPECT AND INFRARED SPECTROSCOPY
!! www.clutchprep.com CONCEPT: PURPOSE OF ANALYTICAL TECHNIQUES Classical Methods (Wet Chemistry): Chemists needed to run dozens of chemical reactions to determine the type of molecules in a compound.
More informationLearning Guide for Chapter 3 - Infrared Spectroscopy
Learning Guide for hapter 3 - Infrared Spectroscopy I. Introduction to spectroscopy - p 1 II. Molecular vibrations - p 3 III. Identifying functional groups - p 6 IV. Interpreting an IR spectrum - p 12
More informationChapter 15 Dienes, Resonance, and Aromaticity
Instructor Supplemental Solutions to Problems 2010 Roberts and Company Publishers Chapter 15 Dienes, Resonance, and Aromaticity Solutions to In-Text Problems 15.2 The delocalization energy is the energy
More informationCan you differentiate A from B using 1 H NMR in each pair?
Can you differentiate A from B using 1 H NMR in each pair? To be NMR active any nucleus must have a spin quantum number, different from zero (I 0) As in 1 H, the spin quantum number (I) of 13 C is 1/2
More informationCHEM1902/4 Worksheet 2: Isomerism and Structure Elucidation Model 4: Isomerism
CHEM1902/4 Worksheet 2: Isomerism and Structure Elucidation Model 4: Isomerism There are three broad classes of isomers. Use the definitions below to help you decide the type of isomerism shown by each
More informationUV-vis (Electronic) Spectra Ch.13 Atkins, Ch.19 Engel
XV 74 UV-vis (Electronic) Spectra-2014 -Ch.13 Atkins, Ch.19 Engel Most broadly used analytical tech / especially bio-applic. inexpensive optics / solvent & cell usually not problem intense transitions
More information1. Predict the structure of the molecules given by the following spectral data: a Mass spectrum:m + = 116
Additional Problems for practice.. Predict the structure of the molecules given by the following spectral data: a Mass spectrum:m + = IR: weak absorption at 9 cm - medium absorption at cm - NMR 7 3 3 C
More informationChem 1075 Chapter 19 Organic Chemistry Lecture Outline
Chem 1075 Chapter 19 Organic Chemistry Lecture Outline Slide 2 Introduction Organic chemistry is the study of and its compounds. The major sources of carbon are the fossil fuels: petroleum, natural gas,
More informationCork Institute of Technology. Summer 2005 Instrumental Analysis (Time: 3 Hours) Section A
Cork Institute of Technology Higher Certificate in Science in Applied Biology Award (National Certificate in Science in Applied Biology Award) Answer FIVE questions; answer Section A, TWO questions from
More informationLecture 11. IR Theory. Next Class: Lecture Problem 4 due Thin-Layer Chromatography
Lecture 11 IR Theory Next Class: Lecture Problem 4 due Thin-Layer Chromatography This Week In Lab: Ch 6: Procedures 2 & 3 Procedure 4 (outside of lab) Next Week in Lab: Ch 7: PreLab Due Quiz 4 Ch 5 Final
More informationUltraviolet Spectroscopy
This work by IJARBEST is licensed under a Creative Commons Attribution 4.0 International License. Available at https://www.ijarbest.com Ultraviolet Spectroscopy 1 D. Farvez Basha, 2 C. Santhiya, 2 K. Tharani
More informationSymmetric Stretch: allows molecule to move through space
BACKGROUND INFORMATION Infrared Spectroscopy Before introducing the subject of IR spectroscopy, we must first review some aspects of the electromagnetic spectrum. The electromagnetic spectrum is composed
More information1.1 Is the following molecule aromatic or not aromatic? Give reasons for your answer.
Page 1 QUESTION ONE 1.1 Is the following molecule aromatic or not aromatic? Give reasons for your answer. 1.2 List four criteria which compounds must meet in order to be considered aromatic. Page 2 QUESTION
More informationFourier Transform Infrared Spectroscopy of Metal Ligand Complexes *
OpenStax-CNX module: m34660 1 Fourier Transform Infrared Spectroscopy of Metal Ligand Complexes * Jiebo Li Andrew R. Barron This work is produced by OpenStax-CNX and licensed under the Creative Commons
More informationPAPER No.12 :Organic Spectroscopy MODULE No.30: Combined problem on UV, IR, 1 H NMR, 13 C NMR and Mass - Part II
Subject Chemistry Paper No and Title Module No and Title Module Tag 12 : rganic Spectroscopy 30: Combined problem on UV, IR, 1 H NMR, 13 C NMR and Mass Part-II CHE_P12_M30 TABLE F CNTENTS 1. Learning utcomes
More information17.1 Classes of Dienes
17.1 Classes of Dienes There are three categories for dienes: Cumulated: pi bonds are adjacent. Conjugated: pi bonds are separated by exactly ONE single bond. Isolated: pi bonds are separated by any distance
More informationCalifornia State Polytechnic University, Pomona
alifornia State Polytechnic University, Pomona 2-1 Dr. Laurie S. Starkey, rganic hemistry M 314, Wade hapter 2: Structure and Physical Properties of rganic Molecules hapter utline 1) rbitals and Bonding
More informationChapter 17: Fundamentals of Spectrophotometry
Chapter 17: Fundamentals of Spectrophotometry Spectroscopy: the science that deals with interactions of matter with electromagnetic radiation or other forms energy acoustic waves, beams of particles such
More information