Specific heat of polysulfur nitride, (SN)x

Measurements of the specific heat of the crystalline metallic polymer (SN)x are reported for the temperature range 1.5≤T≤80deg;K. The lattice contribution to the specific heat deviates from Debye behavior near 4°K, changing from T3 to T2.7 and then to a T dependence as temperature increases. The anisotropy in force constants which cause this behavior is discussed in relation to the crystal structure of (SN)x. From the electronic contribution to the specific heat we estimate an electron band-structure density of states at the Fermi level of 0.14 states/(eV spin molecule). © 1977 The American Physical Society.