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Bottcher, C.

Publications and source records attributed to Bottcher, C..

A constructive model potential method for atomic interactions

A model potential method is presented that can be applied to many electron single centre and two centre systems. The development leads to a Hamiltonian with terms arising from core polarization that depend parametrically upon the positions of the valence electrons. Some of the terms have been introduced empirically in previous studies. Their significance is clarified by an analysis of a similar model in classical electrostatics. The explicit forms of the expectation values of operators at large separations of two atoms given by the model potential method are shown to be equivalent to the exact forms when the assumption is made that the energy level differences of one atom are negligible compared to those of the other.

Bottcher, C.

Nonresonant charge-capture - Na/+/ + Li reversibly proceeding to Na + Li/+/.

The cross sections for the process Na(+) + Li reversibly proceeding to Na + Li(+) are calculated in the range from 100 eV to 12 keV using a perturbed stationary state formulation, and are found to agree with experiment to the extent of reproducing detailed structure. A simple interpretation is presented of the observed quasi-oscillatory structure.

Bottcher, C.

Unified classical path theories of pressure broadening.

Derivation of a unified classical path theory of pressure broadening, using only elementary concepts. It is shown that the theory of Smith, Cooper and Vidal (1969) is only correct at all frequencies to first order in the number density of perturbers.

Bottcher, C.

Potential curves for Na2/+/ and resonance charge transfer cross sections.

A mode potential method, applied earlier to the positively charged diatomic lithium molecule Li2(+), is used to calculate the six lowest potential energy curves of Na2(+). Charge transfer cross sections are calculated for Li(+) on Li and for Na(+) on Na and found to be in reasonable agreement with experiment.

Bottcher, C.