“…The lead nitrate crystal, Pb(NO 3 ) 2 , has cubic symmetry Pa3, with lattice constant a ¼ 7:8586ð2Þ A, volume of the unit cell V ¼ 485:33 A 3 , Z ¼ 4 and density D x ¼ 4:535 g cm À3 [2]. The electric properties of the lead nitrate crystal have been studied [3,4], as well as elastic properties [5,6], thermal properties [3,7], structural properties [2,8] and optical properties and Raman infrared spectra [9,10]. But no evidence for the structural transitions at temperatures from 293.15 to 573.15 K was seen in any of these studies either.…”