ISOTOPE EFFECTS IN THE LATTICE CONSTANT AND THERMAL EXPANSION OF $sup 20$Ne AND $sup 22$Ne SINGLE CRYSTALS.
ISOTOPE EFFECTS IN THE LATTICE CONSTANT AND THERMAL EXPANSION OF $sup 20$Ne AND $sup 22$Ne SINGLE CRYSTALS.
复制标题
$sup 20$Ne 和 $sup 22$Ne 单晶的晶格常数和热膨胀中的同位素效应。
DOI：
10.1103/physrev.173.873
复制
发表时间：
1968
期刊：
影响因子：
--
通讯作者：
R. Simmons
中科院分区：
文献类型：
--
作者：
D. Batchelder;D. Losee;R. Simmons
用定向凝固法生长了Ne 20和Ne 22的单晶，用X射线衍射照相法测定了它们的晶格常数。在2.5至24.3 K的范围内测定热膨胀体积系数，精度范围从低温时的5 ppm K− 1到最高温度时的18 ppm K− 1。外推至0 K的晶格常数对于Ne 20为4.46440 Å*，对于Ne 22为4.45589 Å*，在估计的最大误差0.00008 Å* 范围内。几个当前的晶格动力学模型充分描述了同位素的晶格常数在0 K的差异，而在有限的温度下的描述是不令人满意的。
Single crystals of Ne 20 and Ne 22 were grown by directional solidification from the liquid, and the x-ray lattice constants were measured by means of a rotating-camera method. The volume coefficients of thermal expansion were determined over the interval 2.5 to 24.3 K with a precision ranging from 5 ppm K− 1 at low temperatures to 18 ppm K− 1 at the highest temperature. The lattice constants extrapolated to 0 K are 4.46440 Å* for Ne 20 and 4.45589 Å* for Ne 22, within an estimated maximum error 0.00008 Å*. Several current lattice-dynamical models adequately describe the isotopic difference in the lattice constant at 0 K, while at finite temperatures the description is unsatisfactory.