【摘要】 采用慢度曲面法研究C12H9SN晶体的铁弹相变。在现有实验数据的基础上,模拟计算C12H9SN晶体高温正交相的弹性劲度系数对慢度曲面的影响。结果表明,非对角元c12,c13,c23的变化对慢度曲面最大值的取向没有影响,同时也确定出与该相变直接相关的弹性劲度系数为c55。该晶体相变的对称性变化是由高温正交相mmm点群变成低温单斜相2/m点群。更多还原

【Abstract】 The ferroelastic phase transition of phenothiazine was studied by method of slowness surface.The effect of the stiffness constants on the slowness surfaces of phenothiazine in orthorhombic symmetry was investigated by using experimental data. The result shows that the value of the off-diagonal elements c12,c13,c23 have no effect on the orientation of the maximum slowness. The phase transition in this crystal is just closely related to the stiffness constant c55. The symmetry change of the crystal during the phase transition is that it changes from the group mmm in the higher temperature phase to the group 2 / m in the lower temperature phase.更多还原