Computational energy minimization techniques have been used to study the structure and crystal properties of kaolinite. The full elastic tensors of the sheet silicates of clay have been derived with first-principles c...Computational energy minimization techniques have been used to study the structure and crystal properties of kaolinite. The full elastic tensors of the sheet silicates of clay have been derived with first-principles calculations based on density functional theory. All calculations were performed using GULP program.展开更多
分析了Ba Ti1-xNbxO3(0≤x≤0.04)陶瓷样品中存在的补偿机制及其结构与介电性能的变化。结果表明:Nb5+的掺入没有引起第二相的生成,并能减小陶瓷晶粒尺寸;Nb5+离子的加入有利于Ba Ti O3陶瓷从正常铁电体向弛豫铁电体转变,降低介电常数...分析了Ba Ti1-xNbxO3(0≤x≤0.04)陶瓷样品中存在的补偿机制及其结构与介电性能的变化。结果表明:Nb5+的掺入没有引起第二相的生成,并能减小陶瓷晶粒尺寸;Nb5+离子的加入有利于Ba Ti O3陶瓷从正常铁电体向弛豫铁电体转变,降低介电常数峰值温度(Tm),提高室温介电常数,减小剩余极化强度(Pr)和矫顽场(Ec)。通过Gulp模拟并分析得出当Nb5+掺入后,主要以空位进行补偿,且以钡空位补偿为主,形成缺陷簇。展开更多
文摘Computational energy minimization techniques have been used to study the structure and crystal properties of kaolinite. The full elastic tensors of the sheet silicates of clay have been derived with first-principles calculations based on density functional theory. All calculations were performed using GULP program.
文摘分析了Ba Ti1-xNbxO3(0≤x≤0.04)陶瓷样品中存在的补偿机制及其结构与介电性能的变化。结果表明:Nb5+的掺入没有引起第二相的生成,并能减小陶瓷晶粒尺寸;Nb5+离子的加入有利于Ba Ti O3陶瓷从正常铁电体向弛豫铁电体转变,降低介电常数峰值温度(Tm),提高室温介电常数,减小剩余极化强度(Pr)和矫顽场(Ec)。通过Gulp模拟并分析得出当Nb5+掺入后,主要以空位进行补偿,且以钡空位补偿为主,形成缺陷簇。
