The phase diagram of the solid methanes

Abstract

A comparative study is presented of the phase diagrams of the solid methanes CH4, CH3D, CH2D2, CHD3, and CD4 obtained experimentally using NMR techniques at pressures up to 9 kbar. Polynomial representations of the I–II, I–III and II–III phase transition lines are given. The experimental conditions under which solid methane transforms to phase IV are discussed and polynomial representations of the I–IV, the IV–I, and the IV–II transition lines are also given.