The energies, structures, and vibrational frequencies of M(H2O)n, M = Tl3+, Hg2+, n = 0–9, 18 have been calculated at the Hartree–Fock and second order Møller–Plesset levels of theory using the CEP, LANL2, and SDD effective core potentials in combination with their associated basis sets, or with the 6-31G* and 6-31+G* basis sets. The metal–oxygen distances and totally symmetric stretching frequency of the aqua ions were compared with each other and with solution measurements. The results are consistent with thallium(III) and mercury(II) being hexacoordinate in aqueous solution. The use of symmetry is shown to be advantageous.

中文翻译：

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铊 (III) 和汞 (II) 水合的 Ab Initio 研究

M(H2O)n, M = Tl3+, Hg2+, n = 0–9, 18 的能量、结构和振动频率已使用 CEP、LANL2 在 Hartree-Fock 和二阶 Møller-Plesset 理论水平计算和 SDD 有效核势与其相关的基组或 6-31G* 和 6-31+G* 基组相结合。将水离子的金属-氧距离和完全对称的拉伸频率相互比较并与溶液测量值进行比较。结果与铊（III）和汞（II）在水溶液中是六配位的一致。对称的使用被证明是有利的。