Lattice constants a and c of trigonal selenium between 85 and 380K

The lattice constant a and c of small single crystals of trigonal selenium have been measured by applying the Buerger precession method in the temperature range 85 to 380K. Above 290K, our results agree with previously published data. Within the accuracy of measurement (5*10-3 AA), the temperature dependence of the cell constants is proportional to the temperature in the whole range.