BaFCl：Eu^（2＋）X射线存储机制的探讨

STUDYING OF X-RAY STORAGE PROCESS IN BaFCl:Eu￣(2+)

本文报导了ＢａＦ２－ｘＣｌｘ和ＢＳＦＣｌ：Ｅｕ２－（０．１％）两种粉未样品的制备过程；及其系列样品的电子自旋共振的实验结果．认为ＢａＦＣｌ：Ｅｕ２－存储Ｘ射线的过程是：经Ｘ射线辐照后；在其晶体中形成自由电子和空穴，阴离子空位俘获一个电子形成Ｆ心，而空穴被束缚在两个氯离子上形成Ｖｋ（Ｃｌ２－）心，Ｖｋ（Ｃｌ２－）心经迁移被发光中心Ｅｕ２＋所束缚．

The samples of BaF2-xClx and BaFCl:Eu2+ are prepared.It is proved that F centers and VK(Cl2-)centers exist in the X-irradiated BaF2-xClx by the technique of electron spin resonance.The valent state of Eu2+ in BaFCl: Eu2+ does not change under Xirradiation and unirradiation. From above,the process of X-ray storage is advanced,after X-ray irradiate the sample of BaFCl:Eu2+,free electrons and holes are formed in it.The electrons are trapped in two chlorine ions to form Vk(Cl2-)centers.The VK (Cl2-) centers migrate nearby Eu2+,and finally become the stable VK(Cl2-)centers.