A mixture of two piezochromic compounds can be used as a universal shock detector, i.e., to determine the shock pressure without knowing a priori the temperature at which the shock occurred. For this purpose, both piezochromic compounds must exhibit different temperature influences in their transition-pressure values. This demonstration uses two piezochromic compounds (CoMoO4 and CuMoO4-type oxides) that exhibit a first-order phase transition between their two allotropic forms associated with a drastic color change. The colorimetric coordinates of the mixture indicate the pressure and temperature of a shock.
Keywords: chromogenic; oxides; piezochromic; shock detector.