Structures and electronic properties of amorphous molybdenum-germanium alloys from molecular-dynamics simulations and the tight-binding approximation

Thesis/Dissertation · Thu Jan 01 00:00:00 EST 1987

OSTI ID:5391490

Ding, K

The author developed a set of two-body and three-body potentials for modeling the structure of solid phases of germanium. The potential is of the same functional form as that of Stillinger-Weber for silicon, but it has different values of the parameters. The potential gives an excellent structural representation of amorphous solid Ge as well as crystalline Ge and gives good results for several thermodynamic properties of the crystalline phase and the phonon dispersion relations of the crystal. A set of effective two-body and three-body empirical interatomic potentials are proposed for describing the short-range structure of amorphous alloys of molybdenum and germanium. Molecular-dynamics computer simulation calculations were performed for these alloy for a wide range of compositions using these potentials. The resulting structures have radial distribution functions, differential distribution functions, and partial distribution functions in very good agreement with recent x-ray-scattering experiments of Kortright and Bienenstock for all the compositions studied. The experimental observation is confirmed that MO atoms do not substitute into the germanium random network at low Mo concentrations. Electronic-structure calculations are performed on the amorphous MoGe alloys, using Harrison's universal linear-combination-of-atomic-orbitals parameters to generate Hamiltonians for configurations obtained from the molecular-dynamics simulations.

• Research Organization: Stanford Univ., CA (USA)
• OSTI ID: 5391490
• Resource Relation: Other Information: Thesis (Ph. D.)
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
GERMANIUM ALLOYS
CRYSTAL STRUCTURE
MOLYBDENUM ALLOYS
AMORPHOUS STATE
COMPUTERIZED SIMULATION
DISPERSION RELATIONS
ELECTRONIC STRUCTURE
MOLECULAR MODELS
PHONONS
POTENTIALS
ALLOYS
MATHEMATICAL MODELS
QUASI PARTICLES
SIMULATION
360102* - Metals & Alloys- Structure & Phase Studies
360104 - Metals & Alloys- Physical Properties