Showing papers on "Potential energy surface published in 1985"
TL;DR: In this article, the dynamics of the F+H/sub 2/ reaction have been investigated in a high resolution crossed molecular beam study, and the results strongly suggest that dynamical resonances play a significant role in the reaction dynamics.
Abstract: The dynamics of the F+H/sub 2/ reaction have been investigated in a high resolution crossed molecular beam study. Differential cross sections and kinetic energy distributions were obtained for each HF vibrational state. The v = 1 and v = 2 states were predominantly backward scattered, but substantial forward scattering was observed for HF (v = 3) over the range of collision energies accessible in our apparatus, from 0.7 to 3.4 kcal/mol. The results strongly suggest that dynamical resonances play a significant role in the reaction dynamics of F+H/sub 2/ and that resonance effects are most prominent in the v = 3 product channel. Quantal reactive scattering calculations on F+H/sub 2/ predict that the v = 2 channel should be most strongly affected by resonances. This discrepancy is attributed to inadequacies in the potential energy surface used in the calculations, and several modifications to the surface are proposed based on the experimental results. Other features of the reaction are also discussed, including the integrated partial cross sections, the effect of H/sub 2/ rotation, and the reactivity of F(/sup 2/P/sub 1/2/).
392 citations
TL;DR: In this article, a three-dimensional potential energy surface for the photodissociation of H2O in its lowest excited singlet state A 1B1 in C2v or A 1A″ in C3 symmetry, respectively, has been calculated with quantum-chemical ab initio methods including electron correlation.
135 citations
TL;DR: The adiabatic or Born-Oppenheimer approximation of molecular structure and dynamics has been widely used in the area of molecular physics and chemistry as discussed by the authors, where it has been used to explain a wide range of dynamical processes that lie outside its scope.
Abstract: At the heart of the quantum mechanical description of molecular structure and dynamics lies the adiabatic or Born-Oppenheimer approximation (1 , 2). Starting with an assumption of separability of time scales for nuclear and electronic motion, a familiar picture emerges of nuclei subject to well defined forces corresponding to the potential energy surface for a particular electronic state. Although the well-established success of these ideas in the areas of molecular spectroscopy (3-5) and reaction dynamics (6-9) is likely to secure the adiabatic approximation as a continuing foundation of molecular science, the range of dynamical processes that lies within its scope is far from complete. Recent experimental and theoretical advances in particular are beginning to yield a coherent understanding of several phenomena that, far from requiring minor corrections to the adiabatic approximation for their explanation, by their very nature exist entirely outside its framework. Examples of importance in diverse areas of chemistry and physics range from the dynamics of radiationless decay (1015) and nonadiabatic processes in chemical reactions (16-19) to the spectroscopy of excited (20-23) and ionized (24-26) states of isolated molecules, from single collision electronic energy transfer (27--41) to exciton (42) and soliton (43) dynamics and spin-lattice relaxation (44). Specialized reviews on these topics are available.
101 citations
TL;DR: In this article, an improved analytic potential energy surface for the F+H2→FH+H and H+FH′→HF+H′ reactions is presented, which is more accurate than previous surfaces for thermal rate constants and overall reaction thresholds.
Abstract: We present an improved analytic potential energy surface for the F+H2→FH+H and H+FH′→HF+H′ reactions. The final surface is obtained in two stages. First we create a surface, called No. 4, which is based in the F–H–H barrier region on a previous partly empirical and partly theoretical fit and is based on the F–H⋅⋅⋅H exit channel and H–F–H barrier regions on new large‐basis‐set configuration interaction calculations. The final surface, called No. 5 incorporates more empirical information for collinear geometries in both the F–H–H and FH⋅⋅⋅H regions but remains a good representation of the ab initio calculations for bending potentials and in the strong‐interaction regions. Variational‐transition‐state theory rate constants and WKB adiabatic barrier heights indicate that the final surface is more accurate than previous surfaces for thermal rate constants and overall reaction thresholds for F+H2→HF+H, F+D2→DF+D, and F+HD→HF+D and for product‐state thresholds for HF (n′=3) and DF(n′=4), where n′ is the final vi...
97 citations
TL;DR: A survey of 14 years of theoretical work on the FH/sub 2/ potential energy hypersurface can be found in this paper, where the importance of zero-point vibrational corrections and tunneling corrections in reliable predictions of the same activation energy is discussed.
Abstract: This account surveys 14 years of more or less continuing theoretical research on the FH/sub 2/ potential energy hypersurface. Early encouragement concerning the ability of theory to reliably characterize the entrance barrier for F + H/sub 2/ ..-->.. FH + H has more recently been sobered by the realization that very high levels of theory are required for this task. The importance of zero-point vibrational corrections and tunneling corrections in reliable predictions of the same activation energy is discussed. In contrast, the barrier height of H + FH ..-->.. HF + H three-center exchange stands as a prominent early success of ab initio molecular electronic structure theory. 90 references, 4 figures, 6 tables.
95 citations
TL;DR: In this paper, the authors used variational transition state theory to calculate rate constants and kinetic isotope effects for the reactions F+H2→HF+H (with rate constant k1), F+D2→DF+D(k2), and two other isotopic analogs as functions of temperature.
Abstract: We use variational transition state theory to calculate rate constants and kinetic isotope effects for the reactions F+H2→HF+H (with rate constant k1), F+D2→DF+D(k2), and two other isotopic analogs as functions of temperature. The calculations are performed using a recently proposed partly empirical, partly ab initio potential energy surface, called surface No. 5, and also using a new surface, called surface No. 5A, introduced here to test the effect of a higher classical saddle point on the reaction rates, kinetic isotope effects, and reaction thresholds. The various theoretical results are compared to the available experiments to test the validity of these potential energy surfaces. For those rate constants and kinetic isotope effects for which there is more than one experimental value at a given temperature, the theoretical results for reactions on surface No. 5 agree with experiment about as well as the individual experiments agree with each other. At T>373 K where there is only one experimental measu...
89 citations
15 Feb 1985
TL;DR: In this paper, the potential energy surface for ND3(A¯) molecules in the region of the D2N-D dissociation coordinate was investigated and it was shown that at short separations this surface exhibits a barrier.
Abstract: Electronically excited ND3(A¯) molecules have been prepared by laser two-photon excitation on theA¯1A″2—X¯1′1 transition and monitored via their resulting short-lived emission. The earlier observation of Douglas that ND3(A¯) molecules carrying one quantum of out-of-plane bending vibration ν′2 are least susceptible to predissociation, is confirmed. ND3(A¯) predissociation rates are found to be both vibronic and rovibronic level dependent. Both observations may be understood by considering the likely form of the potential energy surface for ND3(A¯) molecules in the region of the D2N—D dissociation coordinate. At short D2N—D separations this surface exhibits a barrier. The presence of a conical intersection (involving the ND3 ground state surface) further out along the dissociation coordinate has a crucial influence on the magnitude of this barrier. The envisaged form of theA¯-state potential energy surface also provides a qualitative rationale for all previous experimental findings concerning electronic branching ratios and energy disposal amongst the primary photofragments arising in the photodissociation ofA¯-state ammonia.
86 citations
TL;DR: In this paper, an ab initio MCSCF gradient method is applied to explore the potential surfaces of the low-lying excited states of 1, 3 trans-butadiene.
Abstract: Ab initio MCSCF gradient method is applied to explore the potential surfaces of the low‐lying excited states of 1, 3‐trans‐butadiene. The determination of the equilibrium geometries and the force constants shows that there are several local minima for the 1 3Bu (T1), 2 1Ag (S1), and 1 1Bu (S2) states. Since each excited state has a different electronic character, its potential energy surface is complicated with respect to the rotation of C–C double bond and C–C stretching motions. The second 1Ag state is found to have four minima with low symmetry (Ci, C2, and C1). A planar local minimum with C2h symmetry is found on the 1 1Bu surface. The comparable planar minimum was found for the 1 1Bu state of trans‐hexatriene. This is the first ab initio confirmation on the experimental analysis for the planar structure of the state. The present full π space MCSCF calculation gives not only reasonable transition energies but also detailed structures for low‐lying states.
76 citations
TL;DR: In this article, the role of activation barriers in the process of dissociative adsorption of diatomic molecules on metal surfaces is considered in terms of the topology of the diabatic potential energy surfaces of the interacting system.
61 citations
TL;DR: In this article, the authors apply conventional and variational transition state theory with least-action ground state and other transmission coefficients to calculate the rate constants and kinetic isotope effects for the reaction Cl+H2→HCl+H.
Abstract: We apply conventional and variational transition state theory with least‐action‐ground‐state and other transmission coefficients to calculate the rate constants and kinetic isotope effects for the reaction Cl+H2→HCl+H. First we consider collinear reactions and compare the calculated results to accurate quantal results for a given potential energy surface. This tests the dynamical methods and shows that they are reliable enough for testing potential energy surfaces. We then make calculations for the three‐dimensional reactions employing 11 potential energy surfaces that have been proposed in previous work. Seven of the surfaces are extended LEPS surfaces, as proposed by Persky, Klein, and Stern; Truhlar, Magnuson, and Garrett; and Valencich and co‐workers; one is an information‐theoretic‐bond‐order‐plus‐anti‐Morse‐bend surface (called AL/AB) proposed by Agmon, Levine, Truhlar, Magnuson, and Garrett; and the final three surfaces are a diatomics‐in‐molecules‐plus‐three‐center‐terms surface proposed by Baer and Last and two diatomics‐in‐molecules surfaces proposed by Isaacson and Muckerman. Three of the surfaces (the final surface of Persky, Klein, and Stern; the first surface of Truhlar, Magnuson, and Garrett; and the AL/AB surface—all of which have relatively symmetric saddle points) are shown to be more reasonable than the others for predicting the rate constants and the H2/D2 and the HD/DH kinetic isotope effects. The calculations also indicate that the room temperature rate constants are dominated by quantum mechanical tunneling.
50 citations
TL;DR: In this paper, a detailed investigation of rotationally inelastic effects in photodissociation of water in the first absorption band using a recently calculated ab initio potential energy surface of the A 1B1 state was performed.
Abstract: We report a detailed investigation of rotationally inelastic effects in the photodissociation of water in the first absorption band using a recently calculated ab initio potential energy surface of the A 1B1 state. Although the excited state potential anisotropy is large it has only very weak influence on the rotational state distributions which thus simply reflect the angular behavior of the ground state wave function of the parent molecule. The reason is that both potential energy surfaces have roughly the same equilibrium angle. Strong inelastic effects are observed, however, for dissociation out of excited bent states because the corresponding ground state wave function extends over a considerably wider angular range and thus the more anisotropic regions of the excited state potential are probed. Calculations are performed on three levels of accuracy for the continuum wave function: close‐coupling, coupled‐states (CS), and infinite‐order‐sudden (IOS) approximation. The ground state wave function is treated numerically exactly. The CS approximation is found to be extremely reliable for those cases studied in this work. The accuracy of the IOS approximation depends very much on the region of orientation angle probed by the ground state and therefore a general conclusion is not possible. Finally, OH rotational state distributions obtained from the dissociation of water and from H–OH scattering at equivalent translational energies are compared and found to be extremely different.
TL;DR: In this paper, trajectory calculations were performed to understand intramolecular vibrational energy redistribution in tetraallyl tin and carbon, and the results of the trajectory calculations are compared with recent chemical activation studies of molecules containing heavy atoms.
Abstract: Quasiclassical trajectory calculations were performed to understand intramolecular vibrational energy redistribution in tetraallyl tin and carbon. In these calculations a C=C bond initially contains 50, 75, 100, or 125 kcal/mol excess energy, with the remaining modes containing zero‐point energy. For tetraallyl tin the trajectory calculations show rapid intramolecular vibrational energy redistribution within the allyl group containing the excited C=C bond. In contrast, energy transfer beyond the central tin atom is negligible for the initial C=C excitation of 50 kcal/mol. As the excitation is increased, energy transfer past the tin atom is enhanced. However, it is still incomplete within 4 ps for the calculation with a 125 kcal/mol excitation. A ‘‘pure’’ heavy‐atom effect for intramolecular vibrational energy transfer is not observed. Simply substituting carbon for tin in the tetraallyl tin Hamiltonian has no detectable effect on the rate of the energy redistribution. However, energy redistribution is nearly complete within a picosecond for a Hamiltonian with a potential energy surface chosen to more accurately model that a tetraallyl carbon. The results of the trajectory calculations are compared with recent chemical activation studies of molecules containing heavy atoms, and other trajectory studies of intramolecular vibrational energy redistribution.
TL;DR: In this article, the authors calculated state-to-state reaction cross sections for two new energies and state−to−state vibrationally inelastic cross-sections for four energies for H+D2 collisions on the most accurate available potential energy surface.
Abstract: We have calculated state‐to‐state reaction cross sections for two new energies and state‐to‐state vibrationally inelastic cross sections for four energies for H+D2 collisions on the most accurate available potential energy surface. The dynamics calculations are based on the quasiclassical trajectory quadratic smooth sampling method. We present a detailed analysis of the theoretical inelastic and reaction cross sections and compare the trends in the reactive scattering results to those calculated from Gerrity and Valentini’s experiments and extrapolations thereof. The agreement between theory and experiment for the reactive scattering at 0.98–1.3 eV relative translational energy is stupendously good.
TL;DR: In this article, the Schatz-Elgersma analytical fit to the Walsh-Dunning surface was used to obtain the potential energy surface of the H2+OH reaction at 1200 and 2000 K.
Abstract: Classical trajectory calculations have been performed to determine the influence of translational temperature, H2 vibrational energy, H2 rotational energy, OH vibrational energy, and OH rotational energy on the reaction H2+OH→H2O+H. The potential energy surface was a modification of the Schatz–Elgersma analytical fit to the Walsh–Dunning surface. Reactivity increases with translational temperature, and is most strongly influenced by it. Rotational excitation of either or both molecules suppresses reactivity. Vibrational excitation of H2 enhances reactivity, and vibrational excitation of OH has no effect. A thermal rate coefficient was computed for the reaction at 1200 and 2000 K. The computed value compares favorably with the experiment at 2000 K, while the agreement at 1200 K is less satisfactory. The agreement between theory and experiment at both temperatures indicates that the potential surface is a reasonable representation of the HHOH potential energy surface.
TL;DR: In this paper, self-consistent field (SCF) calculations have been carried out at 180 configurations (θ, ϕ′) and distances (R ) for the 4 He-N.
TL;DR: In this article, the H3 + ab initio potential energy surface and its analytical representation has been re-examined to promote more accurate vibration-rotation calculations, and a new and accurate 78 point PNO-CI grid is presented, which predicts the minimum energy geometry to be an equilateral triangle of side, r (H-H) = 1·6525 a 0.
Abstract: The H3 + ab initio potential energy surface and its analytical representation has been re-examined to promote more accurate vibration-rotation calculations. We present here a new and accurate 78 point PNO-CI grid which predicts the minimum energy geometry to be an equilateral triangle of side, r (H-H) = 1·6525 a 0. and energy of -1·34188 E h. Of the analytical representations only the sixth order Simons-Parr-Finlan (SPF) and Ogilvie force fields were found to satisfy our fitting criteria, resulting in associated errors of less than 11·1 kJ mol-1. Our calculated vibrational band origins are in good agreement with those of Carney and Porter, with the differences of the lowest-lying vibration states essentially reflecting the analytical characteristics of the potential energy surfaces used.
TL;DR: In this article, a potential surface for the dissociation of methane CH4 → CH3 + H has been calculated using a 6-13G** basis set and the configuration interaction method.
TL;DR: In this article, the authors applied improved canonical and microcanonical variational transition state theories to the calculation of the rate constants for the polyatomic reaction OH+H2→H2O+H over the temperature range 200-2400 K using the Schatz-Elgersma fit to the Walch-Dunning ab initio potential energy surface.
Abstract: We have applied improved canonical and microcanonical variational transition state theories to the calculation of the rate constants for the polyatomic reaction OH+H2→H2O+H over the temperature range 200–2400 K using the Schatz–Elgersma fit to the Walch–Dunning ab initio potential energy surface. The results are compared to canonical variational transition state theory calculations that employed the same potential energy surface and to experiment. We find that the new results, which are in good agreement with experiment, differ very slightly from those obtained with canonical variational theory. One explanation for this agreement is that the microcanonical variational transition states have a rather weak energy dependence and lie within 0.04a0 of the ground‐state adiabatic barrier maximum. We also find that quantum mechanical effects and the inclusion of reaction‐path curvature are important at lower temperatures, and that the transition state theory treatment of this reaction breaks down for temperatures higher than about 2400 K.
TL;DR: In this article, the rotational and fine structure state distributions of OH produced in the reaction H+O2→OH (N,v, f)+O were probed by fast atom-laser induced fluorescence experiments.
Abstract: The nascent rotational and fine structure state distributions of OH produced in the reaction H+O2→OH (N,v, f)+O were probed by fast atom‐laser induced fluorescence experiments. Translationally hot H atoms were formed by photolysis of HJ and HBr at 248 and 193 nm leading to H+O2 c.m. collision energies E of 2.6, 1.9, and 0.9 eV. The rotational state distributions are compared with trajectory calculations using the ab initio potential energy surface of Melius and Blint. The OH λ‐doublet distributions show preference for the π+ component which increases with increasing E suggesting less importance of out of plane rotation of the HO2 complex at high E. The alignment of OH relative to the flight direction of the H atoms is measured by polarizing analysis and photolysis laser beams. The large polarization effects directly demonstrate that the OH angular momentum vectors are preferentially parallel to the electrical vector of the dissociation laser and perpendicular to the flight direction of the H atoms.
TL;DR: In this paper, a double zeta quality basis set was used for low lying bound and dissociative states of the methoxy radical at C3nu conformations, augmented with polarization and diffuse functions.
Abstract: Accurate, ab initio quantum chemical techniques are applied in the present study of low lying bound and dissociative states of the methoxy radical at C3nu conformations, using a double zeta quality basis set that is augmented with polarization and diffuse functions. Excitation energy estimates are obtained for vertical excitation, vertical deexcitation, and system origin. The rate of methoxy photolysis is estimated to be too small to warrant its inclusion in atmospheric models.
TL;DR: In this paper, a coordinate representation for a potential energy surface is derived using the semiclassical limit of the algebraic Hamiltonian, which provides a direct route from the observed overtone spectrum to a potential.
TL;DR: The method is specialized to the calculation of a conditional saddle point in the liquid-drop model for which the constraint is the mass-asymmetry degree of freedom, useful for cases in which the mass asymmetry is not one of the chosen coordinates but instead is a function of these coordinates.
Abstract: A general method is presented for determining an equilibrium point on a potential energy surface subject to an arbitrary number of constraints. The method is then specialized to the calculation of a conditional saddle point in the liquid-drop model for which the constraint is the mass-asymmetry degree of freedom. This approach is useful for cases in which the mass asymmetry is not one of the chosen coordinates but instead is a function of these coordinates. Conditional saddle points are calculated for the liquid-drop and Yukawa-plus-exponential nuclear energy models, with the nuclear shape parametrized using both a three-quadratic-surface model and a Legendre polynomial expansion of the nuclear surface function. We show how the conditional saddle-point shapes and energies change as the fissility x and the mass asymmetry value ..cap alpha.. are varied. As ..cap alpha.. increases for fixed x, the saddle-point configurations effectively behave like lighter (less fissile) nuclei. For fissilities less than the Businaro-Gallone value (x/sub BG/), the conditional saddle-point energy always decreases with increasing ..cap alpha... For x>x/sub BG/, with increasing ..cap alpha.. the conditional saddle-point energy increases until it reaches the limit of the Businaro-Gallone peak, after which the energy decreases.
TL;DR: The measured reactant and product concentrations during a MeMA BZ oscillator run are given and the observed values for BrMeMA and acetic acid are in fair agreement with the stoichiometric requirement of process 3.
Abstract: numerical values of measured reactant and product concentrations during a MeMA BZ oscillator run are given. Since MeMA is in excess (0.28 M) compared to Br03ions (0.10 M), the stoichiometry of process 3 requires that 0.1 1 M MeMA should be left as deuterated or undeuterated species. This is exactly the result found in our experiment (Table I). Finally, we calculate the concentrations of BrMeMA and acetic acid. From the reacting MeMA (0.17 M), 0.10 M BrMeMA and 0.07 M CH,COOH should be found, when it is assumed that all bromate has reacted. Our observed values for BrMeMA and acetic acid are 0.09 and 0.06 M, respectively (see Table I), which are in fair agreement with the stoichiometric requirement of process 3.
TL;DR: In this article, a DZP-CI barrier of 391 kcal for the cis-AlHCCH --> AlCCH/sub 2/ isomerization has been found.
Abstract: Ab initio molecular electronic structure theory has been used to investigate the Al + C/sub 2/H/sub 2/ potential energy surface Particular emphasis was placed on resolving the apparent conflict between theory and experiment by examining the barrier to rearrangement between cis-AlHCCH (observed by ESR at 4 K) and AlCCH/sub 2/ (theoretically predicted global energy minimum) Analytic self-consistent-field (SCF) gradients were employed with a double-zeta basis set to locate and characterize stationary points on the energy surface Single point CI calculations using a double-zeta + polarization basis set have been carried out at the DZ-SCF stationary points A DZP-CI barrier of 391 kcal for the cis-AlHCCH --> AlCCH/sub 2/ isomerization has been found Such a barrier is clearly prohibitive to this isomerization under the experimental conditions of 4 K By comparing this isomerization to the bare HCCH --> CCH/sub 2/ isomerization, the effect of the aluminum atom has been found to be significant 13 references, 1 figure, 1 table
TL;DR: In this article, the authors used the time-dependent formulation of resonant Raman scattering to elucidate the shape of the excited electronic state potential energy surface, and the dynamics which occur on it immediately following photoexcitation.
Abstract: Resonance Raman spectra of NO2 have been recorded as a function of excitation frequency in the range 0–8000 cm−1 above the predissociation threshold. These spectra are interpreted using the time‐dependent formulation of resonant Raman scattering, to elucidate the shape of the excited electronic state potential energy surface, and the dynamics which occur on it immediately following photoexcitation. Our results show that the dominant optical transition in this spectral range is 2B2–2A1. Our Raman spectra reveal a marked decrease in the dynamical time scale of the predissociation of the 2B2 state as excitation frequency increases. At excitation frequencies approximately 4850 cm−1 above the dissociation threshold, the 2B2 predissociative lifetime becomes comparable to a vibrational period. We have analyzed the resonance Raman spectra, along with the absorption spectrum, to determine the magnitudes of the slopes of the potential surface along the symmetric stretch and bending normal coordinates for the 2B2 ex...
TL;DR: In this article, the authors reported a global potential energy surface with a 2.7 kcal/mol barrier and stretch and bend potentials based on ab initio calculations, which is considerably higher than the 0.7-0.9 kcal/m barriers on recent semi-empirical surfaces.
Abstract: Frisch et al. have estimated, by comparing ab initio potential energy and dynamics calculations to experiment, that the potential energy barrier for the title reaction is 2.7 kcal/mol, which is considerably higher than the 0.7–0.9 kcal/mol barriers on recent semiempirical surfaces we have constructed. In the present article we report a global potential energy surface with a 2.7 kcal/mol barrier and stretch and bend potentials based on ab initio calculations. Variational transition state theory and cross section calculations, based on this surface and including anharmonicity and multidimensional tunneling, are in very poor agreement with experiment, e.g., the thermal rate constant at 190 K is 30 times lower than the experimental value for F+H2 and 35 times lower than the experimental value for F+D2. We also report additional model calculations that pinpoint the reasons for the difference between the results of Frisch et al. and ours. The two main reasons are (i) Frisch et al. approximate the vibrationally ...
TL;DR: In this article, the authors present a fully quantal dynamical study of vibrational relaxation of CO in collisions with H2 treating H2 as a structureless projectile, and demonstrate that on the same level of approximation the present rate constants are about three times larger than those obtained from the potential energy surface of Poulsen.
Abstract: We present a fully quantal dynamical study of vibrational relaxation of CO in collisions with H2 treating H2 as a structureless projectile. The potential energy surface consists of a SCF part, including explicitly the variation with the CO bond distance, and a damped long range dispersion part. This potential model contains only two free parameters in the damping function which have been determined previously by fitting rotationally inelastic beam data for D2–CO. The dynamical calculations are performed within the infinite order sudden approximation (IOSA) and the coupled states approximation (CSA). The IOSA relaxation cross sections are generally a factor of ∼1.5 smaller than the CSA cross sections independent on the initial rotational state of CO for j≲4–6. The relaxation rate constants are very sensitive to small changes of the interaction potential. After readjusting one of the damping parameters (within a range still acceptable with the beam data) the IOSA rate constants agree very well with the experimental ones for ortho H2. It is demonstrated that on the same level of approximation the present rate constants are about three times larger than those obtained from the potential energy surface of Poulsen.
TL;DR: In this paper, the potential energy surface as a function of the rotation angle about the CC bond was investigated and compared with the experimental ESCA spectrum of poly(tetrafluoroethylene).
TL;DR: In this paper, preliminary results for the photodissociation of water within the first absorption band obtained from approximate 3D quantal calculations using an ab initio potential energy surface for the A 1 B 1 state without adjustable parameters.