Room-temperature equation of state of Li2VOSiO4 up to 8.5 GPa

High-pressure single-crystal X-ray diffraction measurements of lattice parameters of the compound Li2VOSiO4, which crystallises with a natisite-type structure, has been carried out to a pressure of 8.54(5) GPa at room temperature. Unit-cell volume data were fitted with a second-order Birch-Murnaghan EoS (BM-EoS), simultaneously refining V0 and K0 using the data weighted by the uncertainties in V. The bulk modulus is K0 = 99(1) GPa, with K′ fixed to 4. Refinements of third order equations-of-state yielded values of K′ that did not differ significantly from 4. The compressibility of the unit-cell is strongly anisotropic with the c axis (K0(c) = 49.7 ± 0.5 GPa) approximately four times more compressible than the a axis (K0(a) = 195 ± 3 GPa).