摘要
本文讨论了ＰｂＴｉＯ３、Ｐｂ１－ｘＬａｘＴｉ１－ｘ／４Ｏ３和Ｐｂ１－ｘＣａｘＴｉＯ３纳米晶拉曼散射中Ａ１（ＴＯ）声子峰的不规则线型和多峰劈裂现象。认为以简正振动坐标构成的非谐性双势阱势能函数和Ｍｏｒｓｅ势能函数的Ｓｃｈｒｄｉｎｇｅｒ方程的解与实验观测到的Ａ１（１ＴＯ）模式在高温下的劈裂峰特征比较一致。从能量角度解释了随ｃ／ａ下降，ωＡ１（ＴＯ）快速向低频移动的原因。
Anomalous lineshape and multiple splitting of A 1(TO) peaks in the Raman Spectra of PbTiO 3, Pb 1-x La xTi 1-x/4 O 3, and Pb 1-x Ca xTiO 3 nanocrystals were observed Normal vibrational coordinates associated with A 1(iTO) mode were used to constitute the anharmonic double welled potential function and the Morse potential energy function. The solutions of the Schrdinger equation were consistent with the experiment data, indicating that at temperature higher than 373K, the A 1(1TO) mode splits into several peaks with freqency in the range of 90cm -1 to 150cm -1 . The reason why the A 1(TO) mode shifts to a lower frequency faster than other phonon modes as the c/a ratio decreases can be explained well from energy consideration.
出处
《光散射学报》
1999年第2期132-136,共5页
The Journal of Light Scattering
基金
黑龙江省自然科学基金
黑龙江大学杰出青年科学基金
关键词
改性
钛酸铅
纳米晶
非谐性
声子模
modified lead titanate
nanocrystal
A 1(TO) phonon
potential energy
anharmonicity
lead titanate
