Molecular dynamics noble gases

Crossed-molecular-beam studies of differential scattering of metastable noble-gas atoms with ground-state noble-gas atoms or simple molecules is the major topic of this chapter. These studies have been carried out recently at several laboratories with the common goal of finding both real and imaginary parts of the interaction potentials to further our understanding of the dynamics of collision processes involving metastable noble-gas atoms. 

In this chapter we summarize the current status of the low-energy scattering of noble-gas metastable atoms in molecular beams. A brief summary of potential scattering theory that is relevant to the understanding of collision dynamics, as well as a description of the experimental method, precedes the presentation of experimental findings. The experimental results presented are mainly from the authors laboratories. 

This review is organized as follows in Sec. 2, the large scale phenomenological physics of meteors is discussed, detailing observations as well as the respective current interpretations. Meteorites will not be discussed in this review. Studies of the chemical and physical processes associated with meteorites have been largely concerned with composition, phase transformations and entrapment of noble gases in the solid meteorites. The reader is referred to several reviews and textbooks on the subject.The elementary gas-phase molecular dynamics relevant to the meteor environment is discussed in Sec. 3, and will primarily focus on the hyperthermal nonequilibrium processes, in concert with the subject matter of this book. 

A molecular dynamics simulation has been performed on 4-n-pentyl-4(-cyanobiphenyl (5CB) in the nematic phase. Order parameters and dipolar couplings have been calculated and used to test theoretical models. Theoretical models have also been developed to explain the shielding of a noble-gas atom in an anisotropic environment and applied to explain the medium-induced shielding of the noble gases Xe and Ne in the nematic liquid crystal 4(-ethoxybenzylidene-4-n-butylaniline (EBBA). ... 

EUich, R., Campbell, E., Knospe, O., Schmidt, R. Collisional dynamics of c60 with noble-gas-atoms studied by molecular dynamics with empirical two- and three-body forces. Zeitschrift fflr Physik D 28, 153-161 (1993). doi 10.1007/BF01436983... 

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