科研之友
微信
新浪微博
Facebook
分享链接
摘要
The paper reports on thorough Raman-scattering study of newly synthesized nanoscale powders of potassium niobate (KNbO3) aimed at evaluating the possible modification of the phase transition temperatures versus the corresponding bulk values. We register a significant expansion of the temperature ranges of all phase transitions, which is attributed to a wide distribution of particle sizes. An average temperature of each phase transition shifts to the high-temperature region differently, namely by 10 degrees, 25 degrees, and 40 degrees, as compared with corresponding transition temperature in bulk crystals of KNbO3 and amounts 0, 248, and 475 degrees C, respectively. In the range from 100 to 110 degrees C, we also find the features, which could be associated with an additional rearrangement of the structure.
- 出版日期2013-4-14
