Resonant ultrasound spectroscopy and comparative studies of a 1-D linear chain (MX) material

Resonant Ultrasound Spectroscopy (RUS) is a measurement technique which utilizes the natural resonance frequencies of a body to determine elastic properties. It may be applied to small (∼mm) samples and measurements can be made over a wide range of temperatures and magnetic fields. If the geometry of the sample is well known we can determine absolute values of elastic moduli for crystals of up to orthorhombic symmetry (9 constants). We have applied RUS to single crystals of the MX material [Pt(en)2I2][Pt(en)2](ClO4)4, where (en) is per-deuterated ethylenediamine. We have observed several anomalies in the behavior of the resonances with temperature which may be associated with phase transitions in the material.