Accession Number : AD0447277

Title :   THEORETICAL INVESTIGATION OF THE ELECTRONIC ENERGY BAND STRUCTURE OF CRYSTALS.

Descriptive Note : Final rept.,

Corporate Author : LOCKHEED MISSILES AND SPACE CO INC SUNNYVALE CA

Personal Author(s) : Herman, Frank

Report Date : JUL 1964

Pagination or Media Count : 31

Abstract : After sketching the present state of theoretical energy band studies, this report concludes that band calculations based on assumed crystal potentials are somewhat out of date, and that further progress will require self-consistent energy band calculations carried out on the basis of clearly defined physical models. Preliminary results for diamond, silicon, germanium, and grey tin based o5 the free-electron exchange model are presented and compared with experiment. These results are the first that actually provide a serious basis for judging the adequacy of this exchange model in applications to valence crystals. Now that the feasibility of full-scale self-consistent band calculations has been decisively demonstrated (in terms of a simplified yet realistic model), it remains to improve various features of the underlying physical model. It will be necessary to adopt a more sophisticated treatment of exchange and correlation effects, and to take relativistic and spin-orbit coupling effects into account. (Author)

Descriptors :   (*CRYSTAL STRUCTURE, ATOMIC ENERGY LEVELS), ATOMIC STRUCTURE, NONMETALS, DIAMONDS, SILICON, GERMANIUM, TIN, POTENTIAL THEORY, VALENCE.

Distribution Statement : APPROVED FOR PUBLIC RELEASE