High-pressure neutron-diffraction studies of KH₂PO₄-type phase transitions as T_c tends to ok

Abstract

A neutron-diffraction study has been carried out on KH₂PO₄ at 16.5kbars and 10K, close to the point at which the transition temperature, T_c, falls to OK at 17.1kbars. The results suggest that under these conditions, the H atoms are still disordered over two sites with a separation, δ, of 0.22(2)Å. Comparison with results from previous structural studies of other other H-bonded systems suggests that T_c is linearly related to δ in each case and that each system has the same critical value of δ as T_c ↪