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在Tl2Ba2Can-1CunO2n+4(n=1,2,3,4)系列超导性氧化物中,Tl2Ba2Ca2Cu3O10具有最高Tc值(125 K)．利用电介质的平均能带模型计算了Tl2Ba2Ca2Cu3O10的局域化学键参数,得到Cu(1)-O键的共价性为0．561,Cu(2)-O键的平均共价性为0．296．应用化学环境因子计算了57Fe在Tl2Ba2Ca2Cu3O10中的穆斯堡尔同质异能位移,证实了57Fe在低掺杂时以Fe3+和Fe4+离子形式占据Cu(1)位置,而在高掺杂时以Fe3+和Fe4+离子形式分别占据Cu(1)和Cu(2)位置．结果表明,化学键理论计算有助于复杂晶体的穆斯堡尔谱的正确分析．
In Tl2Ba2Can-1CunO2n + 4 (n = 1,2,3,4) series superconducting oxides, Tl2Ba2Ca2Cu3O10 has the highest Tc value (125 K). The local chemical bond parameters of Tl2Ba2Ca2Cu3O10 were calculated by using the average energy band model of the dielectric. The covalentness of the Cu (1) -O bond was 0.561, and the average covalentness of the Cu (2) -O bond was 0.296. The Mossbauer isomorphic displacements of 57Fe in Tl2Ba2Ca2Cu3O10 were calculated using chemical environmental factors. It was confirmed that 57Fe occupies the Cu (1) sites in the form of Fe3 + and Fe4 + ions at low doping and Fe3 + And Fe4 + ions occupy Cu (1) and Cu (2) sites, respectively. The results show that the chemical bond theory is helpful for the correct analysis of Mössbauer spectra of complex crystals.