Investigation of H-D isotope effect in a hydrous mineral using neutron diffraction

The isotope fractionation factor is important to discuss the origin of minerals and rocks because it is affected by the environment of where the mineral is formed. Hydrogen and deuterium is known to have a large isotope fractionation that comes from a different in mass. Based on experiments at ambient pressure, Graham et al (1980) indicated the importance of O-H...O geometry on D/H isotope fractionation showing that the mineral with shorter O...O distance of hydrogen bond tends to deplete in deuterium. This result suggests the importance of pressure effect on hydrogen isotope fractionation because the pressure changes the O...O distance in minerals significantly.