| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a fluoride single crystal which has an effective atomic number and a density equal to a BaLu<SB POS="POST">2</SB>F<SB POS="POST">8</SB>single crystal, and can be efficiently produced in accordance with a melt growth method without incurring a phase transformation from anorthorhombic crystal structure to a monoclinic crystal structure. <P>SOLUTION: A fluoride single crystal is provided which is expressed by the chemical formula Ba(M<SB POS="POST">x</SB>Y<SB POS="POST">y</SB>Lu<SB POS="POST">1-x-y</SB>)<SB POS="POST">2</SB>F<SB POS="POST">8</SB>(wherein M is at least one kind of element selected from among Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm and Yb; x is in a range of 0 to 0.5, y is in a range of 0 to 0.8, excluding the case where both x and y are 0) and has a monoclinic crystal structure. The average ion radius of elements M, Y and Lu is from 98.5 to 102.5 pm. <P>COPYRIGHT: (C)2012,JPO&INPIT |
