Decomposition of binary sulphate KHSO4 at high pressure

Pressure induced decomposition (PID) is known to occur only at elevated tem peratures. Here we report its first occurrence at ambient temperature in a binary sulphate, KHSO4 at 4kbar. Raman spectroscopy is used for identifying the decomposition products as K3H(SO4)(2) and H2SO4 from their characteris tic spectra. One of the decomposition products being a liquid is argued to be the reason for the occurrence of the phenomenon at ambient temperature. Other possible decomposition routes are also examined.