Accession Number:

AD0687538

Title:

Elementary Exvitations in FCC Solid Ortho-Hydrogen,

Descriptive Note:

Research communication no. 54,

Corporate Author:

DOUGLAS ADVANCED RESEARCH LABS HUNTINGTON BEACH CALIF

Personal Author(s):

• Raich,John C.
• Etters,Richard D.

Report Date:

1968-04-01

Pagination or Media Count:

61.0

Abstract:

An equation of motion formalism is used to give a nonlinear spin-wave treatment of fcc solid ortho-hydrogen. The elementary excitations in ortho-hydrogen are librational waves, which can be treated in a manner similar to spin-waves in magnetism. The excitation spectrum, long-range order, and ground-state energy are calculated. The spin-wave excitations are found to have a nonvanishing effect on both the long-range order and the ground-state energy. But, because of a large energy gap, the spin-wave theory results deviate only slightly from their molecular field values. Author

Descriptors:

• *SOLIDIFIED GASES
• HYDROGEN
• EXCITATION
• CRYSTAL STRUCTURE
• PHASE STUDIES
• TRANSITION TEMPERATURE
• GROUND STATE
• NONLINEAR SYSTEMS
• PERTURBATION THEORY
• HAMILTONIAN FUNCTIONS
• CRYOGENICS

Subject Categories:

• Atomic and Molecular Physics and Spectroscopy
• Solid State Physics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE