Molecules floppy

The spectra of floppy molecules such as Lij may therefore have different interpretations. For example, the spectra of specific symmetries have been fitted [11] to within a few percent of error by using the simple vibrational normal mode formula... 

Larger, floppy molecules might need to be optimized with a smaller basis set. 

A possible role for shape resonances has been postulated in a number of the photoionization studies mentioned above [52, 53, 57, 60], although it has to be noted that except for camphor [57], the evidence for the existence of the shape resonance is not definitive. (It also then remains an open question how any such resonances, inferred from fixed geometry calculations, would manifest themselves in practice in large, and sometimes floppy, molecules, such as these chiral species.)... 

Floppy molecules, permutational symmetry, dynamic Jahn-Teller and geometric phase effects, 701-711 Floquet theory, geometric phase theory principles of, 33-36... 

Efficient Calculation of Highly Excited Vibrational Energy Levels of Floppy Molecules The Band Origins of Hj up to 35000 cm-1. 

In view of its potential application to the description of floppy molecules,6 it is interesting to quote the result for the expectation value of H in the case where the Hamiltonian is given by... 

Bacic, Z., and Light, J. C. (1989), Theoretical Methods for Rovibrational States of Floppy Molecules, Ann. Rev. Phys. Chem. 40,469. 

Chapuisat, X., and Saint-Espes, C. (1992), A Weak-Mode Representation of Floppy Molecules. H. Kinetic Energy and Total Hamiltonian Matrix, Chem. Phys. 159, 391. 

Chang X-Y, Freed KF (1993) Test of theory for long time dynamics of floppy molecules in solution using Brownian dynamics simulation of octane. J Chem Phys 99(10) 8016—8030 Chompff A J, Duiser JA (1966) Viscoelasticity of networks consisting of crosslinked or entangled macromolecules. I Normal modes and mechanical spectra. J Chem Phys 45(5) 1505-1514... 

A. Application of Canonical Perturbation Theory to Floppy Molecules... 

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