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Specific heat measurements have been carried out in the short range spin correlated phase of the linear antiferromagnet (CH3)4NMnCl3 (TMMC) in order to ascertain effects due to dipolar interactions. The specific heat is linear in T at low temperatures as expected from spin wave theory. The measured coefficient is about one-third the isotropic spin-wave value, but is in better agreement with a prediction from anisotropic spin-wave theory (one-half the isotropic value).

Specific heat measurements on the one-dimensional linear chain antiferromagnet TMMC in the temperature range 0.4–4.0 K show an anomaly at 0.83 K indicative of a three-dimensional magnetic phase transition. Above 0.83 K, that part of the specific heat not related to the phase transition, shows a linear and quadratic dependence on temperature in agreement with measurements at higher (T > 1.5 K) temperatures. The interchain coupling does not appear to be responsible for the observed low value of the linear term. Application of a 15 kG magnetic field along the c-axis broadens the specific heat anomaly and shifts the maximum value from 0.83 K to about 1.0 K.

The electrical resistivity along 500 A thick carbon films has been measured from 1.2 to 1100°K. The electrical resistivity measurements at high temperature indicate a change in the structure of the film beginning at about 670°K. In the theory of non-crystalline solids by Mott, the temperature dependence of the electrical conductivity σ, at low temperature, is given by In σ = A —BT−14 where A and B are constants. Whereas previous investigators have shown general agreement with Mott's relation, the present result at low temperature shows deviation from the In σ α T−14 relation.