Electronic and Photoelectron Spectroscopy: Fundamentals and Case Studies

by Andrew M. Ellis , Miklos Feher , Timothy G. Wright

• ISBN13: 9780521817370
• ISBN10: 0521817374
• Format: Hardcover
• Copyright: 2005-02-14
• Publisher: Cambridge University Press

Summary

Electronic and photoelectron spectroscopy can provide extraordinarily detailed information on the properties of molecules and are in widespread use in the physical and chemical sciences. Applications extend beyond spectroscopy into important areas such as chemical dynamics, kinetics and atmospheric chemistry. This book provides the reader with a firm grounding of the basic principles and experimental techniques employed. The extensive use of case studies effectively illustrates how spectra are assigned and how information can be extracted, communicating the matter in a compelling and instructive manner. Topics covered include laser-induced fluorescence, resonance-enhanced multiphoton ionisation, cavity ringdown and ZEKE spectroscopy. The book is for advanced undergraduate and graduate students taking courses in spectroscopy and will also be of use to anyone encountering electronic and/or photoelectron spectroscopy during their research.

Table of Contents

Preface	xi
List of journal abbreviations	xiii
Part I Foundations of electronic and photoelectron spectroscopy	1	(64)
1 Introduction	3	(4)
1.1 The basics	3	(2)
1.2 Information obtained from electronic and photoelectron spectra	5	(2)
2 Electronic structure	7	(5)
2.1 Orbitals: quantum mechanical background	7	(4)
References	11	(1)
3 Angular momentum in spectroscopy	12	(3)
4 Classification of electronic states	15	(9)
4.1 Atoms	15	(2)
4.2 Molecules	17	(6)
References	23	(1)
5 Molecular vibrations	24	(16)
5.1 Diatomic molecules	24	(7)
5.2 Polyatomic molecules	31	(8)
References	39	(1)
6 Molecular rotations	40	(11)
6.1 Diatomic molecules	40	(3)
6.2 Polyatomic molecules	43	(8)
7 Transition probabilities	51	(14)
7.1 Transition moments	51	(5)
7.2 Factorization of the transition moment	56	(8)
References	64	(1)
Part II Experimental techniques	65	(46)
8 The sample	67	(8)
8.1 Thermal sources	67	(1)
8.2 Supersonic jets	68	(4)
8.3 Matrix isolation	72	(2)
References	74	(1)
9 Broadening of spectroscopic lines	75	(3)
9.1 Natural broadening	75	(1)
9.2 Doppler broadening	76	(1)
9.3 Pressure broadening	77	(1)
10 Lasers	78	(9)
10.1 Properties	78	(1)
10.2 Basic principles	79	(2)
10.3 Ion lasers	81	(1)
10.4 Nd:YAG laser	81	(1)
10.5 Excimer laser	82	(1)
10.6 Dye lasers	83	(2)
10.7 Titanium:sapphire laser	85	(1)
10.8 Optical parametric oscillators	86	(1)
References	86	(1)
11 Optical spectroscopy	87	(15)
11.1 Conventional absorption/emission spectroscopy	87	(2)
11.2 Laser-induced fluorescence (LIF) spectroscopy	89	(3)
11.3 Cavity ringdown (CRD) laser absorption spectroscopy	92	(2)
11.4 Resonance-enhanced multiphoton ionization (REMPI) spectroscopy	94	(2)
11.5 Double-resonance spectroscopy	96	(1)
11.6 Fourier transform (FT) spectroscopy	97	(4)
References	101	(1)
12 Photoelectron spectroscopy	102	(11)
12.1 Conventional ultraviolet photoelectron spectroscopy	102	(3)
12.2 Synchrotron radiation in photoelectron spectroscopy	105	(1)
12.3 Negative ion photoelectron spectroscopy	105	(2)
12.4 Penning ionization electron spectroscopy	107	(1)
12.5 Zero electron kinetic energy (ZEKE) spectroscopy	107	(3)
12.6 ZEKE-PFI spectroscopy	110	(1)
Reference	110	(1)
Further reading	110	(1)
Part III Case Studies	111	(2)
13 Ultraviolet photoelectron spectrum of CO	113	(7)
13.1 Electronic structures of CO and CO+	113	(2)
13.2 First photoelectron band system	115	(1)
13.3 Second photoelectron band system	115	(1)
13.4 Third photoelectron band system	116	(1)
13.5 Adiabatic and vertical ionization energies	116	(1)
13.6 Intensities of photoelectron band systems	117	(1)
13.7 Determining bond lengths from Franck-Condon factor calculations	118	(1)
References	119	(1)
14 Photoelectron spectra of C02, OCS, and CS2 in a molecular beam	120	(9)
14.1 First photoelectron band system	123	(2)
14.2 Second photoelectron band system	125	(1)
14.3 Third and fourth photoelectron band systems	126	(1)
14.4 Electronic structures: constructing an MO diagram from photoelectron spectra	126	(2)
References	128	(1)
15 Photoelectron spectrum of NO-/2	129	(9)
15.1 The experiment	129	(1)
15.2 Vibrational structure	130	(2)
15.3 Vibrational constants	132	(1)
15.4 Structure determination	132	(2)
15.5 Electron affinity and thermodynamic parameters	134	(1)
15.6 Electronic structure	134	(3)
References	137	(1)
16 Laser-induced fluorescence spectroscopy of C3: rotational structure in the 300 nm system	138	(6)
16.1 Electronic structure and selection rules	138	(3)
16.2 Assignment and analysis of the rotational structure	141	(2)
16.3 Band head formation	143	(1)
References	143	(1)
17 Photoionization spectrum of diphenylamine: an unusual illustration of the Franck-Condon principle	144	(6)
References	149	(1)
18 Vibrational structure in the electronic spectrum of 1,4-benzodioxan: assignment of low frequency modes	150	(7)
18.1 Ab initio calculations	152	(1)
18.2 Assigning the spectra	152	(4)
References	156	(1)
19 Vibrationally resolved ultraviolet spectroscopy of propynal	157	(8)
19.1 Electronic states	159	(1)
19.2 Assigning the vibrational structure	159	(2)
19.3 LIF spectroscopy of jet-cooled propynal	161	(3)
References	164	(1)
20 Rotationally resolved laser excitation spectrum of propynal	165	(6)
20.1 Assigning the rotational structure	165	(2)
20.2 Perpendicular versus parallel character	167	(1)
20.3 Rotational constants	168	(1)
20.4 Effects of asymmetry	168	(2)
References	170	(1)
21 ZEKE spectroscopy of AI(H20) and Al(D20)	171	(9)
21.1 Experimental details	172	(1)
21.2 Assignment of the vibrationally resolved spectrum	172	(3)
21.3 Dissociation energies	175	(2)
21.4 Rotational structure	177	(1)
21.5 Bonding in Al(H20)	178	(1)
References	179	(1)
22 Rotationally resolved electronic spectroscopy of the NO free radical	180	(7)
References	186	(1)
23 Vibrationally resolved spectroscopy of Mg+-rare gas complexes	187	(10)
23.1 Experimental details	188	(1)
23.2 Preliminaries: electronic states	189	(1)
23.3 Photodissociation spectra	190	(1)
23.4 Spin-orbit coupling	190	(3)
23.5 Vibrational assignment	193	(1)
23.6 Vibrational frequencies	194	(1)
23.7 Dissociation energies	195	(1)
23.8 B-X system	196	(1)
References	196	(1)
24 Rotationally resolved spectroscopy of Mg+-rare gas complexes	197	(8)
24.1 X²Σ+ state	197	(2)
24.2 A²Π state	199	(1)
24.3 Transition energies and selection rules	200	(1)
24.4 Photodissociation spectra of Mg+-Ne and Mg+-Ar	201	(3)
References	204	(1)
25 Vibronic coupling in benzene	205	(3)
25.1 The Herzberg-Teller effect	208	(2)
References	209	(1)
26 REMPI spectroscopy of chlorobenzene	210	(6)
26.1 Experimental details and spectrum	211	(1)
26.2 Assignment	212	(3)
References	215	(1)
27 Spectroscopy of the chlorobenzene cation	216	(7)
27.1 The X²B¹ state	216	(5)
27.2 The B state	221	(1)
References	222	(1)
28 Cavity ringdown spectroscopy of the α¹Δ[-X³Σ-/g transition in O2 223
28.1 Experimental	223	(2)
28.2 Electronic states of O2	225	(1)
28.3 Rotational energy levels	226	(1)
28.4 Nuclear spin statistics	227	(1)
28.5 Spectrum assignment	228	(1)
28.6 Why is this strongly forbidden transition observed?	229	(1)
References	229	(1)
Appendix A Units in spectroscopy	230	(2)
A.1 Some fundamental constants and useful unit conversions	231	(1)
Appendix B Electronic structure calculations	232	(11)
B.1 Preliminaries	232	(2)
B.2 Hartree-Fock method	234	(3)
B.3 Semiempirical methods	237	(1)
B.4 Beyond the Hartree-Fock method: allowing for electron correlation	238	(1)
B.5 Density functional theory (DFT)	239	(1)
B.6 Software packages	240	(1)
B.7 Calculation of molecular properties	240	(2)
References	242	(1)
Further reading	242	(1)
Appendix C Coupling of angular momenta: electronic states	243	(6)
C.1 Coupling in the general case: the basics	244	(1)
C.2 Coupling of angular momenta in atoms	244	(2)
C.3 Coupling of electronic angular momenta in linear molecules	246	(2)
C.4 Non-linear molecules	248	(1)
Further reading	248	(1)
Appendix D The principles of point group symmetry and group theory	249	(17)
D.1 Symmetry elements and operations	249	(2)
D.2 Point groups	251	(1)
D.3 Classes and multiplication tables	252	(2)
D.4 The matrix representation of symmetry operations	254	(2)
D.5 Character tables	256	(1)
D.6 Reducible representations, direct products, and direct product tables	257	(2)
D.7 Cyclic and linear groups	259	(2)
D.8 Symmetrized and antisymmetrized products	261	(1)
Further reading	261	(1)
Selected character tables	262	(4)
Appendix E More on electronic configurations and electronic states: degenerate orbitals and the Pauli principle	266	(3)
E.1 Atoms	266	(2)
E.2 Molecules	268	(1)
Appendix F Nuclear spin statistics	269	(3)
E 1 Fermionic nuclei	270	(1)
F.2 Bosonic nuclei	270	(2)
Appendix G Coupling of angular momenta: Hund's coupling cases	272	(5)
G.1 Hund's case (a)	272	(2)
G.2 Hund's case (b)	274	(2)
G.3 Other Hund's coupling cases	276	(1)
Further reading	276	(1)
Appendix H Computational simulation and analysis of rotational structure	277	(5)
H.1 Calculating rotational energy levels	277	(2)
H.2 Calculating transition intensities	279	(1)
H.3 Determining spectroscopic constants	279	(1)
References	280	(1)
Further reading	281	(1)
Index	282