We calculated all 2967 even and odd bound states of the adiabatic ground state of NO2 , using a modification of the ab initio potential energy surface of Leonardi et al. [J. Chem. Phys. 105, 9051 (1996)]. The calculation was performed by harmonic inversion of the Chebyshev correlation function generated by a DVR Hamiltonian in Radau coordinates. The relative error for the computed eigenenergies...

Highly accurate potential energy functions for the HeI and HeBr molecules have been calculated using an ab initio treatment that included basis set extrapolation to the complete basis set, as well as spin-orbit coupling in the ground 2sigma+ and first 2pi excited doublet states. The rovibronic bound state energies and resonance lifetimes were also evaluated by a Prony analysis of the autocorrel...

The empirical observation that homologous proteins fold to similar structures is used to enhance the capabilities of an ab initio algorithm to predict protein conformations. A penalty function that forces homologous proteins to look alike is added to the potential and is employed in the coupled energy optimization of several homologous proteins. Significant improvement in the quality of the com...

The dependence of the spin-orbit-coupling constant of the six low-lying electronic states of Ar2(+) and Kr2(+) on the internuclear distance R has been calculated ab initio. The spin-orbit-coupling constant varies by about 10% over the range of internuclear distances relevant for the interpretation of the high-resolution photoelectron spectra of Ar2 and Kr2 and can be accurately represented by a...

Five-dimensional ab initio potential energy surfaces (PESs) for CO(2)-H(2) that explicitly incorporate dependence on the Q(3) asymmetric-stretch normal-mode coordinate of the CO(2) monomer and are parametrically dependent on its Q(1) symmetric-stretch coordinate have been calculated. Analytic four-dimensional PESs are obtained by least-squares fitting vibrationally averaged interaction energies...

Theory is developed for the calculation of dipole transition line strengths and frequencies for rotational and ro-vibrational transitions from wavefunctions expressed in the generalized body-fixed co-ordinates proposed by Sutcliffe and Tennyson (1986, Molec. Phys., 58, 1053). Computations using this theory produce calculated frequencies for the fundamental ro-vibrational transitions of H2 D+ an...

Extensive ab initio calculations were performed for the X̃ 2E′ and à 2E′′ states of Ag3, using a newly constructed basis set for Ag. An important goal of these calculations is to guide the analysis of the experimentally observed à 2E′′-X̃ 2E′ electronic spectrum. Vibrational frequencies of Ag3 for both the X̃ and à state are reported. Spectroscopically obtainable parameters describing the Jahn-Tel...

Based on a first-principles approach, we present scaling rules for the band gaps of graphene nanoribbons (GNRs) as a function of their widths. The GNRs considered have either armchair or zigzag shaped edges on both sides with hydrogen passivation. Both varieties of ribbons are shown to have band gaps. This differs from the results of simple tight-binding calculations or solutions of the Dirac's...