Nuclear Magnetic Resonance Determination of Some Microscopic Parameters of LiAl5O8
Nuclear Magnetic Resonance Determination of Some Microscopic Parameters of LiAl5O8
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LiAl5O8部分微观参数的核磁共振测定
DOI：
10.1063/1.1725432
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发表时间：
1964
影响因子：
4.4
通讯作者：
G. Stauss
中科院分区：
文献类型：
--
作者：
G. Stauss
通过对单晶和多晶LiAl_5 O_8中~ 7 Li和~（27）Al的NMR谱的分析，获得了四极耦合数据。在轴对称站点上，|νQ| ~ 7 Li和~（27）Al分别为41± 2kc/sec和284±6 kc/sec。在具有八面体配位的27 Al位上，|νQ| =683±25 kc/sec，η=0.347±0.025，找到了主轴的取向，离子模型计算给出了晶体偏离理想尖晶石形式的畸变的估计和νQ值的可能符号。给出了二阶位移的一个方便的一般表达式，以及多晶样品线形中突出的二阶特征的位置结果。
Quadrupole coupling data have been obtained from analysis of NMR spectra of 7Li and 27Al in single crystal and polycrystalline ordered LiAl5O8. On axially symmetric sites, values of | νQ | for 7Li and 27Al are, respectively, 41±2 kc/sec and 284±6 kc/sec. On 27Al sites with octahedral coordination, | νQ |=683±25 kc/sec, η=0.347±0.025, and the orientation of principal axes has been found. An ionic model calculation gives estimates of distortions of the crystal from the ideal spinel form and possible signs for the νQ values. A convenient general expression for second‐order shifts is given, together with results for the positions of the prominent second‐order features in the line shapes of polycrystalline samples.