Neutron-scattering study of low-energy excitations in some organic glass formers

The results of inelastic incoherent neutron-scattering measurements of solid phases of isopentyl cyanobiphenyl (5*CB), isooctyloxy cyanobiphenyl (8*OCB), cyclooctanol and glycerol are presented. Low-energy excitations in glassy phases were observed both as a boson peak in direct geometry measurements and as an excess density of states in inverted geometry experiments. The mechanism of the phenomenon is suggested.