Abstract: For pt.I see ibid., vol.11, p.113 (1980). The 4f and valence states of all metallic rare earths have been studied using X-ray photoelectron spectroscopy (XPS) for the occupied part and bremsstrahlung isochromat spectroscopy (BIS) for the unoccupied part. It is found that the bandwidth increases from Gd to Lu, and that the valence band spectra are in fair agreement with APW calculations. The intensities of the 4f final-state multiplets are well described in terms of the coefficients of fractional parentage. There is a symmetry between the fn XPS and f14-n BIS spectra. The observed energies of the 4f excitations correspond to transitions to completely screened final states. These values enable one to predict the elements which are liable to interconfiguration fluctuation when their 4f levels are shifted to EF by the chemical environment or by compression. The large Coulomb correlation energies, U, which prevent the formation of 4f bands in these elements, are directly obtained from the authors' spectra, and are found to be in good agreement with recent calculations. The linewidths and singularity indices of the XPS and BIS 4f lines are determined and discussed.

Abstract: We have developed a theory for the properties of vibrational excitations in molecules adsorbed on a metal surface. The coherent potential approximation (CPA) is used in the treatment of the vibrational interaction between the molecules. We show, by interpreting infrared spectra of substitutionally disordered systems consisting of isotopic mixtures of CO on Cu(100), that the molecules interact mainly through their dipole fields. We also show that in interpreting the integrated absorptance in infrared spectroscopy or the relative loss intensity in electron-energy-loss spectroscopy it is necessary to take into account the screening due to the electronic polarizability of the adsorbed molecules. A simplified version of the CPA result is used for a discussion of the absorption spectra of partial monolayers of one isotope. With the assumption that the CO molecules are randomly distributed, comparison between theory and experiment indicates that the dipole-dipole interaction alone is responsible for the coverage-dependent frequency shift for CO adsorbed on a transition metal [Ru(001)], whereas there is an almost equally large counteracting chemical shift on a noble metal [Cu(100)]. The meaning and origin of the dynamical dipole moment of adsorbed CO molecules are discussed. We find that the increase of the dynamical dipole moment (by a factor 2-3) upon adsorption probably is due to charge oscillations between CO $2{\ensuremath{\pi}}^{*}$ molecular orbitals and the metal. Finally, we outline how the theory developed here can be applied to a fundamental step in photosynthesis.

Abstract: Under suitable circumstances imperfections in semiconductors can bind electrons (holes) with a binding energy small compared to the intrinsic energy gap of the host; the wavefunctions characterising the energy levels of the imperfection are extended over many lattice spacings. This review discusses the electronic energy levels of chemical impurities in the classic group IV elemental and the III-V and II-VI compound semiconductors. The large dielectric constant of the host, the anisotropic effective mass tensor and/or the small effective mass of the charge carrier are the factors which play a significant role in the description of the electronic energy levels; they can be viewed as scaled-down versions of the hydrogen atom with bound states having binding energies orders of magnitude smaller than those of the hydrogen atom. The authors present the experimental results on the spectroscopy of donors and acceptors in semiconductors together with the theory necessary for their interpretation. They discuss the experimental results and the theory of the bound states of impurities in the context of the symmetry and the effective-mass parameters of the band extrema with which they are associated. Effects of external perturbation-piezo- and magneto-spectroscopy-are presented both from experimental and theoretical points of view. The review concludes with the experimental observations on the linewidths of the excitation spectra of donors and acceptors in semiconductors and an analysis of the causes underlying them.

Abstract: Optical spectroscopy of electronic centers in solids.- Excitation transfer in disordered systems.- Dynamics of incoherent transfer.- General techniques and experimental methods in laser spectroscopy of solids.- High resolution laser spectroscopy of ions in crystals.- Laser excited fluorescence spectroscopy in glass.- Excitation Dynamics in Molecular Solids.- Addendum (to the Second Edition).

Abstract: Application of vibrational spectroscopy to the problem of structure determination of molecules of biological interest goes back to the early uses of raman and infrared spectroscopy in the study of organic molecules. For reviews of earlier work the reader is referred to compilations by Kohlrausch (1943) and by Jones and Sandorfy (1956), whereas more recently a comprehensive discussion has been presented by Bellamy (1975). These compilations accentuate the correlation of vibrational spectra with molecular structure from an essentially empirical point of view and culminate in the establishment of empirical correlation charts. For typical examples the reader is referred to Weast (1974) and Bellamy (1975). There have been many treatments of the theoretical basis of molecular vibrational spectroscopy. Among them the classical work by Herzberg (1945) and by Wilson et al. (1955) should be mentioned. Applications of infrared spectroscopy (IR) to structure problems of biological interest have been summarized by Susi (1969), Fraser and MacRae (1973), and Wallach and Winzler (1974). It was remarked quite eraly that relevant structural information about biological systems often requires study in aqueous solution, which forms the natural environment for most biologically important systems. Besides critical control of experimental conditions and samples the conventional methods of raman spectroscopy may be applied to aqueous solutions in a quite straightforward manner, cf. the contribution by Lord and Mendelson, Chapter 8.

Abstract: 1 The history of matrix isolation spectroscopy- Section A - Techniques- 2 Infrared and Raman matrix isolation spectroscopy- 3 Electronic spectroscopy of matrix isolated solutes- 4 Magnetic circular dichroism - matrix isolation spectroscopy- 5 Electron spin resonance studies of radicals trapped in rare-gas matrices- 6 Moessbauer spectroscopy on matrix-isolated species- 7 Time and frequency resolved vibrational spectroscopy of matrix isolated molecules: Population and phase relaxation processes- 8 Stable molecules- 9 Generation and trapping of unstable solutes in low temperature matrices- 10 The characterisation of high temperature molecules using matrix isolation and vibrational spectroscopy- 11 High pressure studies- 12 Non-traditional matrix isolation: adducts- Section B - Matrix Effects- 13 Interpretation of infrared and Raman spectra of trapped molecular impurities from interaction potential calculations- 14 Matrix induced changes in the electronic spectra of isolated atoms and molecules- 15 Matrix effects studied by electron spin resonance spectroscopy- 16 Molecular motion in matrices- 17 Vibrational band intensities in matrices- Section C - Applications- 18 Matrix isolation spectroscopy of metal atoms and small clusters- 19 Vibrational spectra of matrix isolated gaseous ternary oxides- 20 Matrix isolation spectra (IR, Raman) of transition metal compounds- 21 Metal carbonyls - structure, photochemistry, and IR lasers- 22 Matrix isolation vibrational spectroscopy on organic molecules- 23 Conformational isomerism studied by matrix isolation vibrational spectroscopy- 24 Hydrogen bonding in matrices- Author Index

Abstract: Energy level data are given for the atom and all positive ions of sodium (Z = 11). These data have been critically compiled, mainly from published material on measurements and analyses of the optical spectra. We have derived or recalculated the levels for a number of the ions. In addition to the level value in cm−1 and the parity, the J value and the configuration and term assignments are listed if known. Leading percentages from the calculated eigenvectors are tabulated wherever available. Ionization energies are given for all spectra.

Abstract: XPS studies and infrared absorption measurements of the reactively sputtered (RS) amorphous SixC1–x: H alloy system have been made. The binding energy of the Si 2p core electrons decreases monotonically as the alloy composition x increases while the corresponding line-width remains almost constant. On the other hand, a curve of the C 1s core electron binding energy versus x has a kink at around x = 0·5∼0·6. Infrared absorption spectra reveal the existence of C–H, Si–H, Si–C bonds in the films. These results are discussed in terms of chemical bonding states.

Abstract: The optical absorption, emission, emission lifetime, and absolute quantum efficiency have been measured for chromium (III) in a wide variety of oxide and fluoride glasses. In all cases, the room temperature emission is dominated by inhomogeneously broadened 4T2 fluorescence, and the relaxation of this level is shown to be primarily nonradiative. Multiphonon emission to lattice modes, concentration quenching, and quenching by hydroxyl moieties is shown not to be of significance in this relaxation at low doping levels. Instead, it is proposed that the radiationless process involves primarily local modes associated with the CrX6 cluster and is sensitive to site symmetry.

Abstract: This and the following paper describe the practical application of recently developed, two-dimensional nuclear magnetic resonance techniques for studies of proteins. In the present report spin-echo-correlated spectroscopy and two-dimensional J-resolved spectroscopy are used to identify complete spin systems of non-labile, aliphatic protons in the basic pancreatic trypsin inhibitor. Overall, 41 out of the 58 aliphatic spin systems in this protein were identified; for the first time the spin systems of all the glycyl residues in a protein have been identified in the 1H NMR spectrum. Combined with the following paper, the present data yield new individual assignments for numerous amino acid residues and provide a new avenue, based on accurate measurements of spin-spin coupling constants in the two-dimensional J-resolved spectra, for studying changes of static and dynamic aspects of protein conformation between single crystals and solution, or between different conditions of solvent and temperature.

Abstract: The dynamics of the photodissociation of the NO2 molecule into NO(X 2Π1/2,3/2; v, J)+O(3P0,1,2) at the N2 laser wavelength 337 nm (=29 965 cm−1) has been investigated by laser photofragment spectroscopy at room temperature in bulk. The internal energy distribution of the NO(X 2Π) fragment has been analyzed state selectively with respect to the electronic energy (Ω=1/2, 3/2) and rotation–vibration energy (v, J) using laser induced fluorescence excitation for the NO observation by the A–X transition in the ultraviolet. The rotational and vibrational populations strongly deviate from equilibrium distribution indicating a nonstatistical decay mechanism. The partitioning of the maximum available excess energy of 4842 cm−1 is about 70% into internal and 30% into recoil fragment energy. The distribution of the internal energy is about 51% into vibration and 16% into rotation of NO, with an inversion in the vibrational population of the accessible levels v=0,1,2.

Abstract: Crossed laser pulse excitation generates high amplitude, counterpropagating, ultrasonic waves (acoustic phonons of selected wave vector) via direct coupling between the optical electromagnetic field and the material acoustic field. The technique allows optical generation of ultrasonic waves, conveniently tunable to at least 20 GHz. The coupling mechanism, which does not involve optical absorption, is discussed in detail in terms of electrostriction. The periodic density changes resulting from the acoustic waves cause spectral shifts whose magnitudes reflect the strengths of excited-state intermolecular interactions and excited-state phonon interactions. The first quantitative measurements of spectral shifts by laser-induced phonon spectroscopy (LIPS) are reported. In pentacene in $p$-terphenyl, spectral shifts on the order of 1 ${\mathrm{cm}}^{\ensuremath{-}1}$ are measured using laser-induced phonons propagating along the $b$ crystallographic axis. Orientation of the phonon wave vector along various crystalline directions allows investigation of the anisotropic excited-state intermolecular interactions.

Abstract: Doppler shift laser induced fluorescence spectroscopy was used to determine the relative sputtering yields and number density velocity distribution of sputtered neutral ground state zirconium atoms. Neither change in primary ion energy over the range 1–3 keV nor change in primary ion mass (Ar+, Kr+) affected the velocity distribution despite large changes in the sputtering yield. The measured number density velocity distributions n(v) are well explained by standard linear collision cascade theory and follow the expression n(v)dv α [v2/(v2+v2b)3]dv, where vb is the velocity corresponding to a surface binding energy, Eb = 1/2mZrv2b, with Eb = 6.305 eV, the bulk zirconium sublimation energy. Surprisingly, the number density velocity distributions of zirconium atoms sputtered in two excited states (a 3F3,4) are indistinquishable from that measured for ground state zirconium atoms. Further, the sputtering yield dependence on primary ion energy for the 3F3,4 was also, within experimental error, the same as for ...

Abstract: A measurement based on the fast-atomic-beam separated-oscillatory-field method of sub-natural-linewidth spectroscopy gives, for the Lamb shift in hydrogen, $\mathcal{S}(n=2)=1057.845(9)$ MHz. The result is not in good agreement with theory.

Abstract: The gas-phase extinction-coefficient spectra of ten fluorosubstituted benzenes are presented and compared with benzene in the region 4.5-9.5 eV. The three singlet-singlet transitions analogous to the B2u from A1g, B1u from A1g and E1u from A1g transitions of benzene are presented and discussed. The appearance of the elusive 1E2g state is reported in 1,3,5-TFBz and two tetrafluorobenzenes, while in monofluorobenzene and o-DFBz the 3s and 4s members of the 1E1g Rydberg state are detected. From this work the authors conclude that they have the following order for benzene: 1B2u<1B1u<3s(1E1g)<1E1u