PHONONS IN AMORPHOUS AND RHOMBOHEDRAL ARSENIC

The energy distribution of vibrational modes in a threefold continuous random network containing only even-membered rings of atoms has been calculated and is here compared with that obtained earlier for a network containing both odd- and even-membered rings. Parameters appropriate to amorphous arsenic were used. In addition the density of states for rhombohedral arsenic has been calculated using an increasing ratio for the strength of interlayer-intralayer bonding. The spectra are discussed with regard to various experimental results obtained from neutron, infrared and Raman spectroscopy for amorphous and crystalline forms of arsenic. © 1979.