Ab initio calculation of the rotational spectrum of methane vibrational ground state

Ab initio calculation of the Hoyle state.

The Hoyle state plays a crucial role in the helium burning of stars heavier than our Sun and in the production of carbon and other elements necessary for life. This excited state of the carbon-12 nucleus was postulated by Hoyle as a necessary ingredient for the fusion of three alpha particles to produce carbon at stellar temperatures. Although the Hoyle state was seen experimentally more than a...

Ab initio interaction potential of methane and carbon dioxide: Calculation of second-virial coefficient

An interaction potential at different orientation for the CH4 and CO2 complex was derived at theB3LYP level of theory and 6-31+G* basis sets. The potential energy surface was computed on somemolecular geometries. The complete basis set limit of the interaction energies were fitted to wellknownanalytical functions. To determine the second virial coefficients B, U(r) is used to obtain themodel’s ...

On-the-Fly ab Initio Semiclassical Calculation of Glycine Vibrational Spectrum

We present an on-the-fly ab initio semiclassical study of vibrational energy levels of glycine, calculated by Fourier transform of the wavepacket correlation function. It is based on a multiple coherent states approach integrated with monodromy matrix regularization for chaotic dynamics. All four lowest-energy glycine conformers are investigated by means of single-trajectory semiclassical spect...

Ab initio vibrational-rotational spectrum of potassium cyanide: KCN. II. Large amplitude motions and rovibrational coupling

.4b initio vibrational-rotational spectrum of potassium cyanide: KCN

Dynamical calculations are performed on an ab initio potential energy surface for KCN. Approximate variational solutions of the vibrational Eckart hamihonian are presented for several states. Fundamental vibrations are found to lie at 302.7 cm -1 and 119.7 cm -1. An effective rotational hamihonian is solved for several vibrational states allowing vibrational assignments to be made to the observ...