Chemical bonding in sulfur, selenium, and tellurium fromI129andTe125Mössbauer investigations
Chemical bonding in sulfur, selenium, and tellurium fromI129andTe125Mössbauer investigations
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I129 和 Te125 穆斯堡尔研究中硫、硒和碲的化学键合
DOI：
10.1103/physrevb.19.3187
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发表时间：
1979
影响因子：
3.7
通讯作者：
P. Boolchand
中科院分区：
文献类型：
--
作者：
C. Kim;P. Boolchand
塑性和正交Te x S 1−x(x=0.0 1)，三角非晶，单斜Te Se 1−x(x≤0.0 1 6)，用Te m 12 9标记源研究了三角Te。从这些数据中，我们得到了I杂质的化学键信息，并表明它在所有这两个配位的主体中几乎都是单配位的。此外，在比较硫族主族中测量的I129四极耦合和已知的Te 125四极耦合时，两个耦合的比率出现了一个系统的模式。首先，VZZ的符号反转被认为发生在从Te到I的过程中，并且被证明是化学键重排的结果。Te的π-键轨道与两个硫族近邻的双重配位转变为I的σ-键轨道与硫族近邻的近单配位。Te 125-I129四极耦合的比值R分别为：T-Te(-1.12)，t-Se(-0.65)，m-Se(-0.55)，a-Se(-0.52)，r-S(-0.48)，p-S(-0.48)。R的大小从Te到S的系统降低被证明是主体化学键的日益分子性的证据。通过对不同晶型Se之间成键的对比，表明a-Se是这些固体中分子量最大的。A-Se的成键比t-Se的更接近于m-Se的成键。
I 129 Mössbauer spectra of plastic and orthorhombic Te x S 1− x (x= 0.01), trigonal, monoclinic, and bulk amorphous Te x Se 1− x (x≤ 0. 0 1 6), and trigonal Te have been investigated using Te m 129 labeled sources. From these data, we obtain chemical-bonding information of the I impurity, and show that it is nearly onefold coordinated in all these twofold coordinated hosts. Further, in comparing the measured I 129 quadrupole couplings to the known Te 125 quadrupole couplings in the chalcogen hosts, a systematic pattern in the ratios of the two couplings emerges. First, a sign reversal of V zz is believed to occur in going from Te to I, and is shown to be a consequence of chemical-bonding rearrangement, viz. the twofold coordination of Te involving π-bonding orbitals with two chalcogens near neighbors, transforms into a nearly onefold coordination of I involving σ-bonding orbitals with a chalcogen neighbor. Second, the ratios R of the Te 125-I 129 quadrupole couplings are found to be as follows: t-Te (-1.12), t-Se (-0.65), m-Se (-0.55), a-Se (-0.52), r-S (-0.48), and p-S (-0.48). The systematic reduction in the magnitude of R from Te to S is shown to be evidence of an increasingly molecular character of the host chemical bonding. In contrasting the bonding between the Se polymorphs, it is shown that a-Se is the most molecular of these solids. The bonding in a-Se is shown to be much closer to that in m-Se than in t-Se.