Elastic Constants and Ultrasonic Attenuation of aβ-Tungsten-StructureV3Ge Crystal from 4.2 to 300°K

摘要: The longitudinal and transverse acoustic velocities the ultrasonic attenuation of a $\ensuremath{\beta}$-tungsten ${\mathrm{V}}_{3}$Ge crystal with structure have been measured by pulse technique at frequency 10 MHz between 4.2 300\ifmmode^\circ\else\textdegree\fi{}K. room-temperature elastic moduli determined as ${C}_{11}=2.966$, ${C}_{44}=0.6978$, ${C}_{12}=1.042$ in units ${10}^{12}$ dyn/${\mathrm{cm}}^{2}$. Contrary to behavior $\ensuremath{\beta}$-tungsten-structure compounds ${\mathrm{V}}_{3}$Si ${\mathrm{Nb}}_{3}$Sn, adiabatic compressibility was found be temperature-dependent. constant ${C}_{12}$ exhibits lattice-softening phenomenon temperature interval 75 shear modulus $\frac{1}{2}({C}_{11}\ensuremath{-}{C}_{12})$ displays minimum 75\ifmmode^\circ\else\textdegree\fi{}K. At this (in contrast shear) shows sharp peak. is discussed terms possible operation an electron transfer mechanism. In addition, both behave anomalously 168\ifmmode^\circ\else\textdegree\fi{}K. A relaxational process assumed. limiting value Debye 487\ifmmode^\circ\else\textdegree\fi{}K. room temperature, it 471\ifmmode^\circ\else\textdegree\fi{}K.