Nuclear quadrupole double resonance study of ferroelectric phase transitions

Abstract

The temperature dependence of the ¹⁷O and ¹⁴N NQR frequencies have been measured in PbHPO₄ and diglycine nitrate with the help of nuclear quadrupole double resonance. In addition the proton-oxygen distance has been determined in diglycine nitrate from the dipolar structure of the NQR lines. The results are used to discriminate between different mechanisms driving the phase transitions.