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15 Jun 1978

Volume 68, Issue 12, pp. 5305-5672

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Geminal nuclear spin–spin couplings in ABn‐type molecular systems

Eiko Hiroike

J. Chem. Phys. 68, 5305 (1978); http://dx.doi.org/10.1063/1.435706 (4 pages) | Cited 3 times

Online Publication Date: 11 August 2008

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An approximate formula for the second‐order perturbation energy previously obtained by the author is applied to the calculation of geminal nuclear spin–spin couplings in ABn‐type molecular systems. It is shown why the electron correlation is unusually important in the geminal couplings. The signs of cis and trans geminal couplings are discussed for the AB6‐type molecular systems.
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33.25.+k Nuclear resonance and relaxation

Energy transfer in A 2Σ+ OH. II. Vibrational

Russell K. Lengel and David R. Crosley

J. Chem. Phys. 68, 5309 (1978); http://dx.doi.org/10.1063/1.435707 (16 pages) | Cited 82 times

Online Publication Date: 11 August 2008

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Vibrational energy transfer within the A 2Σ+ state of OH and OD has been studied. A frequency doubled tunable dye laser excites individual N′, J′ levels in v′=1 or 2, and the intensities of rotationally resolved fluorescence emitted in the presence of collision partners (He, Ar, H2, D2, and N2) furnished state‐to‐state transfer rates. It is found that the transfer rates are strongly dependent on initial rotational level (decreasing as Ni increases), that the final rotational state distributions are near thermal but hot, that isoenergetic transfer is small, and that the magnitudes for transfer 1→0, 2→1, and 2→0 are all similar. The rates themselves are large; for example, with N2, k1→0 (Ni=3) =1.7×10−10 cm3 sec−1. The results, taken together, are supportive of a long‐lived collision in which anisotropic attractive forces are of importance in the dynamics of the entrance channel.
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34.50.Ez Rotational and vibrational energy transfer

Temperature dependence of electron spin‐lattice relaxation of methyl radicals in glassy organic matrices:Relation to environmental dynamics and radical decay

Jacek Michalik and Larry Kevan

J. Chem. Phys. 68, 5325 (1978); http://dx.doi.org/10.1063/1.435708 (6 pages) | Cited 10 times

Online Publication Date: 11 August 2008

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The electron spin‐lattice relaxation of trapped methyl radicals in methanol , 2−methyltetrahydrofuran, and 3−methylhexane glasses has been directly studied as a function of temperature from 5‐100 K by the saturation recovery method. The relaxation rate remains fast at low temperatures and shows a large component linear in temperature. This is interpreted in terms of the recently developed model of tunneling relaxation involving modulation of the electron nuclear dipolar interaction by tunneling of nuclei in the radical’s environment [J.Phys.Chem.81,456 (1977)]. Deuteration experiments show that CH3 and [J.Phys.Chem.81,456 (1977)]. Deuteration experiments show that CH3 and CD3 have the same relaxation rate while it is decreased by about four−fold by deuterating the matrix. There also appears to be a correlation between the spin‐lattice relaxation rate and the decay of methyl radicals in these matrices.
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76.30.Rn Free radicals
81.05.Kf Glasses (including metallic glasses)

An ESR study of the CH2ClCO radical at 77 K in x‐irradiated chloroacetamide crystals

B. Kalyanaraman and L. D. Kispert

J. Chem. Phys. 68, 5331 (1978); http://dx.doi.org/10.1063/1.435709 (5 pages) | Cited 3 times

Online Publication Date: 11 August 2008

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X‐irradiation of chloroacetamide crystals at 77 K yields at least two radicals which are not stable near 300 K. One of these give rise to a four line ESR spectrum due to two nonequivalent protons with the principal hyperfine tensor components for H (1) equal to 268.4, 260.3, and 256.1 MHz and for H (2) equal to 129.9, 109.7, and 109.9 MHz. The principal g values are gmax=2.0674, gint=2.0144, and gmin=1.9909. Comparing the corresponding direction cosines to selected molecular directions obtained from an x‐ray crystal structure as well as deuteration studies suggests the species to be the π‐radical CH2ClCO. The unpaired electron is largely distributed between the oxygen and carbon 2p orbitals whose symmetry axis lies perpendicular to the CCO plane. Crystallographically, the chlorine atom lies nearly in the CCO plane and does not give rise to any resolvable ESR hyperfine couplings. The second radical gives rise to a complex ESR spectrum which has been tentatively assigned as due to ⋅CH2Cl. This radical decays upon warming above 100 K with the resultant formation of ĊHClCONH2.
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76.30.Rn Free radicals
61.80.Cb X-ray effects
31.15.bu Semi-empirical and empirical calculations (differential overlap, Hückel, PPP methods, etc.)
33.35.+r Electron resonance and relaxation

Vibrational normal modes of SiO2. III. α‐Berlinite (AlPO4) and its relations to Γ–A phonon dispersion curves in α‐quartz

J. Etchepare and M. Merian

J. Chem. Phys. 68, 5336 (1978); http://dx.doi.org/10.1063/1.435710 (6 pages) | Cited 6 times

Online Publication Date: 11 August 2008

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The valence force field, previously obtained to describe the vibrational normal modes of quartz, cristobalite, and tridymite forms of SiO2 (parts I and II), has been used to calculate the phonon dispersion curves and elastic constants of α‐quartz. The reasonably good fit to the experimental data suggested that the same valence force field may be valid in α‐berlinite, an isomorph of α‐quartz. The following results confirm the analogy between SiO2 and AlPO4.
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63.20.D- Phonon states and bands, normal modes, and phonon dispersion
62.20.D- Elasticity

An EPR–ENDOR study of phosphorus in phenacite

R. C. DuVarney and A. K. Garrison

J. Chem. Phys. 68, 5342 (1978); http://dx.doi.org/10.1063/1.435711 (6 pages) | Cited 2 times

Online Publication Date: 11 August 2008

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An EPR and ENDOR study on a phosphorus impurity in natural single crystals of phenacite (Be2SiO4) is reported. The EPR studies on this strongly coupled electron–nuclear spin system include the forbidden or ΔMF=0 transitions. The nuclear g factor of the impurity ion which was calculated from an analysis of the forbidden transitions shows the impurity to be 31P. The principal values and directions of the electronic g tensor and the hyperfine coupling tensor were determined through a least‐squares fit to the data employing direct diagonalization of the Hamiltonian matrix. ENDOR studies show a superhyperfine (shf) coupling of this center to several near neighbor 9Be nuclei. The shf coupling parameters for three 9Be nuclei were determined and are presented along with a detailed model of the center and a discussion of the crystallographic positions of the Be nuclei. Our analyses indicate a P5+ ion substitutes for a Si ion at a normal site and is converted to P4+ by x rays.
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76.30.He Platinum and palladium group (4d and 5d) ions and impurities (Zr-Ag and Hf-Au)
76.70.Dx Electron-nuclear double resonance (ENDOR), electron double resonance (ELDOR)
61.05.C- X-ray diffraction and scattering

Light scattering from spheroids in shear flows. I. The orientation correlation

Claude Cohen and L. Gary Leal

J. Chem. Phys. 68, 5348 (1978); http://dx.doi.org/10.1063/1.435712 (9 pages) | Cited 9 times

Online Publication Date: 11 August 2008

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The time dependent orientation distribution function for ellipsoids of revolution (a,b,b) in shear flow is obtained as an expansion in terms of the parameter r=[1−(b/a)2]/[1+(b/a)2]. Our results reduce to Peterlin’s steady state results at infinite time (t=∞). Using this distribution, the orientation correlation function and its contribution to the light spectrum of polarized light are calculated. The results for the correlation function as an expansion in r lead also simultaneously to an expansion in the ratio σ of the shear rate to the Brownian rotation diffusion coefficient, σ=γ/D. The expansion procedure is thus valid for reasonably high shear rates in the case of nearly spherical spheroids (r≪1) or for small shear rates but large values of r (‖r‖?1, rods and disks).
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78.35.+c Brillouin and Rayleigh scattering; other light scattering
36.20.-r Macromolecules and polymer molecules

Exchangeable proton couplings in free radicals: Radiation products of hydroxyproline HCl

Ching‐Lung Ko and Harold C. Box

J. Chem. Phys. 68, 5357 (1978); http://dx.doi.org/10.1063/1.435713 (6 pages) | Cited 12 times

Online Publication Date: 11 August 2008

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Free radicals were generated by X irradiation in single crystals of hydroxyproline HCl irradiated at low temperature. Proton hyperfine couplings were deduced from ENDOR measurements on two species, namely, a primary reduction product and a secondary free radical formed in a hydrogen abstraction process. These two radicals are representative of two general types of radicals, one nearly planar and the other markedly pyramidal, in which the unpaired electron interacts with nonexchangeable β protons attached to carbon and exchangeable β protons attached to oxygen. The characteristics of the hyperfine coupling tensors of these protons are discussed.
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82.50.-m Photochemistry
76.70.Dx Electron-nuclear double resonance (ENDOR), electron double resonance (ELDOR)

Theory of elasticity of polymer networks. II. The effect of geometric constraints on junctions

Burak Erman and Paul J. Flory

J. Chem. Phys. 68, 5363 (1978); http://dx.doi.org/10.1063/1.435714 (7 pages) | Cited 56 times

Online Publication Date: 11 August 2008

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The effects of junction–chain interactions in a real network are analyzed in terms of a model in which the entanglements restricting fluctuations of the junctions are represented by vertical‐wall potential domains. Within these domains the junctions are allowed to fluctuate freely. The domains are assumed to transform linearly with macroscopic strain. The additional stress that arises due to the restrictions on the fluctuations of junction points accounts for the principal departures of experimental stress–strain curves from phantom‐network theory. The size of the entanglement domain, which is the only arbitrary parameter introduced, measures the deviations of the real network from phantom network theory. Calculations based on this model show the reduced force to be approximately independent of strain in the compression region (α<1) and to decrease approximately linearly with the reciprocal of the elongation α in tension (α≳1) over the range accessible to experiment.
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62.20.D- Elasticity
36.20.Fz Constitution (chains and sequences)

Spectroscopic characterization of ytterbium monohalide emission in a high pressure electrodeless microwave arc discharge

Jerry Kramer

J. Chem. Phys. 68, 5370 (1978); http://dx.doi.org/10.1063/1.435715 (8 pages) | Cited 8 times

Online Publication Date: 11 August 2008

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Molecular emission has been observed in high‐pressure electrodeless microwave arc discharges from the monochloride, monobromide, and monoiodide of ytterbium. The vibrational analyses of the electronic transitions in YbBr and YbI represent the first spectroscopic data for these molecules. Emission from the A (2Σ1/2) →X (2Π+) and A (2Π+) and R (2Π3/2) →X (2Σ+) transitions in YbCl have been observed. By analogy with YbF and YbCl, the blue degraded emission in YbBr and YbI has been assigned to the A (2Π1/2) →X (2Σ+) and A (2Π3/2) →X (2Σ+) transitions. The term values for YbBr and YbI are shifted to the red with respect to YbCl by <100 cm−1 and <300 cm−1, respectively, for both transitions. The spin–orbit coupling constants of the A (2Π) state in YbBr and TbI have been determined from the difference in the band origins of the two A→X transitions. The effect of the lanthanide contraction in the ytterbium monohalides has been examined by comparing the ground state vibrational frequencies of the ytterbium monohalides and the Group IIa monohalides. Finally, the spectra of YbCl observed under high‐pressure arc conditions have been compared to the YbCl emission previously observed in a low‐pressure chemiluminescent beam experiment.
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33.15.Mt Rotation, vibration, and vibration-rotation constants
52.80.Pi High-frequency and RF discharges
33.20.Kf Visible spectra

Theory for BCl3+H2 laser induced chemistry

B. Kivel

J. Chem. Phys. 68, 5378 (1978); http://dx.doi.org/10.1063/1.435701 (5 pages) | Cited 3 times

Online Publication Date: 11 August 2008

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The experimental data of Rockwood and Hudson are analyzed in terms of a binary collision mechanism for H2+BCl3→BHCl2 +HCl. The model assumes the atom interchange occurs during the collision and uses the known rate for H2+Cl→HCl+H to explain the experimental results. A qualitative account is given for the dependence of yield of BHCl2 on flux and gas pressure.
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33.80.Rv Multiphoton ionization and excitation to highly excited states (e.g., Rydberg states)
33.80.Wz Other multiphoton processes
82.30.Cf Atom and radical reactions; chain reactions; molecule-molecule reactions
82.30.Hk Chemical exchanges (substitution, atom transfer, abstraction, disproportionation, and group exchange)
82.40.Bj Oscillations, chaos, and bifurcations

A one‐dimensional model for exciton motional correlation effects in dense triplet exciton systems

D. B. Chesnut and S. R. Bondeson

J. Chem. Phys. 68, 5383 (1978); http://dx.doi.org/10.1063/1.435702 (9 pages) | Cited 2 times

Online Publication Date: 11 August 2008

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A model for motional correlation effects of random‐walking particles with spin in one dimension is developed. For a system of particle site density ρ, the hard sphere interactions between particles are modeled by considering a single particle moving on a line segment of length ρ−1 undergoing perfectly elastic reflective collisions at the end points of the lattice; the collision rate is used to determine the spin exchange rate. The model is applied to proton spin–lattice relaxation in the MTPA(TCNQ)2 triplet exciton ion radical salt. Using mean theoretical estimates for the anisotropy parameters, a jump rate νj is calculated indicative of an activated process with an activation energy of approximately 0.12 eV ith a preexponential factor of the order of 1.5×10+14 Hz. Limitations and extensions of the model are discussed.
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71.35.-y Excitons and related phenomena
76.60.Es Relaxation effects

Ring puckering in the 1B2(n, 3s) Rydberg electronic state of cyclobutanone

C. R. Drury‐Lessard and D. C. Moule

J. Chem. Phys. 68, 5392 (1978); http://dx.doi.org/10.1063/1.435703 (4 pages) | Cited 2 times

Online Publication Date: 11 August 2008

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The first vacuum ultraviolet absorption spectrum of cyclobutanone has been photographed under conditions of moderately high resolution. This system, which is given the assignment ?1B2(n, 3s) ←?1A1, has been observed to have unusually discrete rotational and vibrational fine structure. To higher frequencies from a weak (0–0) band are a pair of weak vibronic bands at (+105) and (+196) cm−1 which are assigned to the ring puckering sequence transitions (1–1) and (2–2). From a fit of the energy levels derived for the upper state to a quartic–quadratic potential function it was determined that the C1C2C3C4 carbon atoms are coplanar in this state. The increase in puckering frequency from 35 to 140 cm−1 is interpreted in terms of a large increase in ring strain on excitation.
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33.20.Ni Vacuum ultraviolet spectra

The kinetics of solvent reorientation in hydroxylated solvents from the exciting‐wavelength dependence of chromophore emission spectra

John G. Milton, Robert M. Purkey, and William C. Galley

J. Chem. Phys. 68, 5396 (1978); http://dx.doi.org/10.1063/1.435704 (9 pages) | Cited 11 times

Online Publication Date: 11 August 2008

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The disappearance of the exciting‐wavelength dependence of the phosphorescence spectra of polar, aromatic chromophores in supercooled glycol–water mixtures is utilized to monitor the kinetics of solvent reorientation. Reorientation times in the nanosecond to second range are obtained for (3:2 v/v) glycerol–water and (1:1 v/v) ethylene glycol–water at 140–240 °K. The results suggest that the process is one involving a cluster of solvent molecules and in which the chromophore plays a relatively passive role. Steady‐state data and direct measurements of phosphorescence shifts as a function of time indicate that the solvent reorientation process is nonexponential in nature. The decay function derived from the temperature dependence of the steady state data is consistent with the decays observed directly as a function of time. Interpretation of this nonexponential decay in terms of a summation of rate processes leads to a distribution dominated by two reorientation rate constants. The relative contributions of the slow and faster reorientation rate constants in addition to their activation parameters differ for the glycerol–water and ethylene glycol–water mixtures.
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33.50.Dq Fluorescence and phosphorescence spectra
31.70.Dk Environmental and solvent effects
82.20.Pm Rate constants, reaction cross sections, and activation energies

The structures of cis‐polyacetylene and highly conducting derivatives

R. H. Baughman, S. L. Hsu, G. P. Pez, and A. J. Signorelli

J. Chem. Phys. 68, 5405 (1978); http://dx.doi.org/10.1063/1.435705 (5 pages) | Cited 126 times

Online Publication Date: 11 August 2008

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The structures of cis‐polyacetylene and polyacetylene–iodine derivatives have been investigated by x‐ray diffraction and crystal packing analysis. Results obtained for cis‐polyacetylene are consistent with the space group Pnma with one CH per asymmetric unit and a chain symmetry (m1)t. Hence, the structure is analogous to that of orthorhombic polyethylene. For a structure with such a concentration of π electrons there is minimal overlap between parallel π orbitals. The π orbitals are almost orthogonal for four of the six closest neighbors of a given chain. Based on x‐ray diffraction and spectroscopic results, a model is proposed for the structure of the highly conducting polyacetylene–iodine complexes. According to this model, linear arrays of polyhalide ions (principally in the form of I−3) substitute in positions of displaced polyacetylene chains. At high dopant concentrations, alternate close‐packed layers of polyacetylene are separated by a layer consisting of such polyhalide arrays. This model predicts a limiting charge transfer of 0.11 electron on the average per carbon atom in the polyacetylene chain.
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61.41.+e Polymers, elastomers, and plastics
61.05.C- X-ray diffraction and scattering

The temperature dependence of the rate constant for Cl+NO+N2 → NOCl+N2

J. H. Lee, J. V. Michael, W. A. Payne, and L. J. Stief

J. Chem. Phys. 68, 5410 (1978); http://dx.doi.org/10.1063/1.435716 (4 pages) | Cited 3 times

Online Publication Date: 11 August 2008

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The rate constant for the reaction Cl+NO+N2→k1 ClNO+N2, of interest in stratospheric chemistry, has been measured by the flash photolysis–resonance fluorescence technique over the temperature range 200–400 K. The measured rate constants obey the Arrhenius equation k1,N2= (1.18±0.10) ×10−32 exp[(532±20)/T] cm6 molecule−2 sec−1. At room temperature with the two additional third bodies, He and Ar, the measured termolecular rate constants are k1,He= (4.11±0.20) ×10−32 and k1,Ar= (4.40±0.30) ×10−32 cm6 molecule−2 sec−1. These results are theoretically discussed and are compared with previous work.
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82.20.Pm Rate constants, reaction cross sections, and activation energies
82.33.Tb Atmospheric chemistry

Rate constants for the reactions of O−, O2−, NO2−, CO3−, and CO4− with HCl and ClO− with NO, NO2, SO2, and CO2 at 300 K

I. Dotan, D. L. Albritton, F. C. Fehsenfeld, G. E. Streit, and E. E. Ferguson

J. Chem. Phys. 68, 5414 (1978); http://dx.doi.org/10.1063/1.435717 (3 pages) | Cited 13 times

Online Publication Date: 11 August 2008

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The rate constants for several ion–molecule reactions involving chlorine‐containing ions or molecules have been measured at 300 K with a flowing afterglow apparatus. These include the reaction of O− with CCl4, several negative ions with HCl, ClO− with several neutrals, and Cl− with O3. These reactions are used to place limits on the electron affinity of ClO: E.A.(ClO) =1.95±0.25 eV. The implications of these results to the negative ion chemistry of the atmosphere are discussed.
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82.20.Pm Rate constants, reaction cross sections, and activation energies
82.33.Tb Atmospheric chemistry

Semiempirical theory of chemisorption on narrow d‐band metals

G. Doyen and G. Ertl

J. Chem. Phys. 68, 5417 (1978); http://dx.doi.org/10.1063/1.435718 (18 pages) | Cited 38 times

Online Publication Date: 11 August 2008

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A previous developed model is applied to chemisorption of various adsorbates on Ni, Cu, Pd, and Ag surfaces. The aim of the calculations was mainly to predict the trends of various physical properties over a series of different adsorption systems. Adsorption energies, ionization energies, and energy profiles are evaluated and compared with experiment. The difference photoelectron spectra are derived to a first approximation by including the optical matrix elements for excitation into plane wave final states. Chemisorption of atomic hydrogen and oxygen is treated in detail. In the case of hydrogen chemisorption the results agree qualitatively well with conclusions drawn from more elaborate numerical calculations published recently. For oxygen chemisorption the importance of the multiplet structure of the O atom is stressed. In this model the large exchange splitting of the O 2p level is preserved in the adsorbed state; the main effect caused by coupling to the metal is a screening shift by about 8 eV towards lower ionization energies. The earlier treated adsorbates CO, NO, and N2 are included in the concluding discussion which attempts to extract the dominating physical aspects. Comparison with experimental data is generally encouraging.
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68.43.-h Chemisorption/physisorption: adsorbates on surfaces

A Monte Carlo study of the classical octopolar solid

Seamus F. O’Shea

J. Chem. Phys. 68, 5435 (1978); http://dx.doi.org/10.1063/1.435719 (7 pages) | Cited 11 times

Online Publication Date: 11 August 2008

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A Monte Carlo simulation of the effect of temperature on the structure of the classical octopolar solid predicts the existence of three phases. The structures are identical with those predicted by the molecular field method but the transition temperatures are significantly different. Results are also given for the energy, specific, and lattice correlation functions as a function of temperature.
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61.50.Ah Theory of crystal structure, crystal symmetry; calculations and modeling

Wien effect in mixed strong electrolytes

Mou‐shan Chen

J. Chem. Phys. 68, 5442 (1978); http://dx.doi.org/10.1063/1.435720 (6 pages)

Online Publication Date: 11 August 2008

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A method of Fourier transformations and matrix representations is formulated for the computation of Wien effect in diluted solutions of mixed strong electrolytes. The method permits the extension of the computation to systems containing any number of species of ions of any valence type. Thus, for the first time Wien effect of mixed electrolytes is computed from the fundamental equations of ion–ion interactions. At very low field strengths, where Ohm’s law is obeyed, the integral representation of Onsager and Kim is reproduced. At extremely high field strengths, the relaxation effect and the electrophoretic effect are computed to the second order term. At intermediate field strengths, the equations for the computation of the relaxation effect and the electrophoresis by triple integrations are derived.
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82.45.-h Electrochemistry and electrophoresis

G‐intensity sum rule applications: XY3 molecules

Roy E. Bruns and A. B. M. S. Bassi

J. Chem. Phys. 68, 5448 (1978); http://dx.doi.org/10.1063/1.435721 (3 pages) | Cited 4 times

Online Publication Date: 11 August 2008

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Using the pyramidal XY3 (X=N, P; Y=H, F) molecules as examples, the G‐intensity sum rule of Crawford, expressed in terms of effective charges, is shown to be an effective test of the numerical results of vibrational analyses. Errors in previously reported effective charge values for NF3 and PF3 are corrected. Values for the as yet unreported polar tensors of these molecules are presented. Comparisons of these results with those previously reported for other molecules are made.
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33.20.Tp Vibrational analysis

The polar tensors, atomic effective charges, and infrared vibrational intensities of C6H6, C6D6, and C6F6

Benício de Barros Neto and Roy E. Bruns

J. Chem. Phys. 68, 5451 (1978); http://dx.doi.org/10.1063/1.435722 (8 pages) | Cited 9 times

Online Publication Date: 11 August 2008

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The preferred experimental set of signs for the ∂p/∂Qi’s of C6H6 and C6D6 have been determined from the gas phase infrared intensities of these molecules. This set for C6H6 is in agreement with the one found previously for this molecule based on data for C6H6, C6H5D, and p‐C6H4D2. Polar tensors, atomic mean dipole moment derivatives, anisotropies, and effective charges for C6H6, C6D6, and C6F6 are reported. The isotopic invariance of these quantities as indicators of the correct sign choice for the ∂p/∂Qi’s is investigated for C6H6 and C6D6. Several applications of the G‐sum rule are made: (a) its usefulness in pointing out the correct signs of the ∂p/∂Qi is investigated, (b) corrected values for the intensity sums of C6H5D and p‐C6H4D2 are calculated, and (c) intensity sums for C6H4F2 and C6H2F4 are predicted.
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33.70.Fd Absolute and relative line and band intensities
33.20.Ea Infrared spectra

Free atom core binding energies from X‐ray photoelectron spectroscopy. II. Na, K, Rb, Cs, and Mg

M. S. Banna, B. Wallbank, D. C. Frost, C. A. McDowell, and J. S. H. Q. Perera

J. Chem. Phys. 68, 5459 (1978); http://dx.doi.org/10.1063/1.435723 (8 pages) | Cited 43 times

Online Publication Date: 11 August 2008

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Gas phase photoelectron spectra of sodium, potassium, rubidium, cesium, and magnesium have been obtained with AlKα radiation. The binding energies measured are: Na 1s (1079.1 eV), K2p (303.2 eV, 300.5 eV), Rb 3p (254.3 eV, 245.4 eV), Cs 3d (745.8 eV, 731.8 eV), and Mg1s (1311.5 eV). Experimental and theoretical values from the literature have been compared with our results. The free atom binding energies were found to be greater than the comparative solid state binding energies; the differences being: Na 5.1 eV, K 3.6 eV, Rb 3.4 eV, Cs 3.4 eV, and Mg 4.8 eV. The multielectron excitation satellites present in the spectra of these atoms are also discussed.
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32.80.Fb Photoionization of atoms and ions

Studies in fluctuation analysis. II. Injected white noise as a solution to the phase problem of relaxation spectrometry

William O. Romine

J. Chem. Phys. 68, 5467 (1978); http://dx.doi.org/10.1063/1.435724 (4 pages)

Online Publication Date: 11 August 2008

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As a continuation of the first paper in this series, we extend the analysis of the theory for obtaining kinetic rate constants, relaxation times, and Onsager flow coefficients to a macroscopic ’’fluctuation’’ level. The concept is based on the injection of a stochastic Markoffian (Gaussian) white noise as a thermodynamic perturbation in lieu of the classical relaxation approaches involving deterministic signals. As found with the case of microscopic statistics studied in the previous paper, we find that certain relations hold between the rate coefficients and the power spectral matrix, these being as follows: (1) the matrix of rate coefficients is four times the inverse of the ’’normalized’’ power spectrum of the measured reactant fluctuations in reduced (exactly determined) form at the zero frequency extrapolation; (2) the eigenvalues of the normalized spectral matrix at the zero frequency point are the relaxation times; (3) the coefficients of the Onsager ’’flow’’ or ’’conductance’’ matrix L are readily obtained from the spectral matrix inverse, the externally induced second moments, and the calculated intrinsic statistical mechanical second moments. The implications at the experimental level, notably with regard to this approach being a suitable solution to the ’’phase problem’’ of relaxation spectrometry, are discussed.
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05.40.-a Fluctuation phenomena, random processes, noise, and Brownian motion
82.20.Rp State to state energy transfer

Studies of the chemiluminescent reaction Ho+N2O → HoO∗

S. P. Tang, B. G. Wicke, and J. F. Friichtenicht

J. Chem. Phys. 68, 5471 (1978); http://dx.doi.org/10.1063/1.435725 (3 pages)

Online Publication Date: 11 August 2008

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The chemiluminescent spectrum of the reaction Ho+N2O →HoO∗+N2 has been obtained, identifying three excited electronic states populated by the reaction. Each excited state is shown to result from a bimolecular reaction, and the relative chemiluminescent cross section vs kinetic energy for producing each excited state is obtained. The total scattering cross section for Ho+N2O is obtained vs kinetic energy. The total reactive cross section is estimated to be 16±4 Å2.
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34.50.Lf Chemical reactions
34.50.Fa Electronic excitation and ionization of atoms (including beam-foil excitation and ionization)
78.60.Ps Chemiluminescence
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