Compressibilities and Grüneisen constants of the monoxides of titanium, vanadium and niobium

The compressibilities of titanium, vanadium and niobium monoxide have been determined using an X-ray tetrahedral anvil press with NaCl as an internal standard. An extrapolation technique involving the plotting of (da/a)_NaCl versus (da/a)_oxide was developed for eliminating the errors in lattice parameter determination resulting from sample movement within the pressure cell. The Grüneisen constants of the monoxides were evaluated using published specific heat data and our own determinations of thermal expansion.