C_(40)H_4碳氫球簇型分子及C_(40)X_4碳鹵球簇型分子理論計算研究

Theoretical Study of C_(40)H_4 and C_(40)X_4 Cluster Molecules

10.6623/chem.1997014

盧力華(Li-Hwa Lua)；陳成(Cheng Chen)；孫光中(Kuang-Chung Sun)

C_(40)球簇型分子 ； C_(40)H_4碳氫球簇型分子 ； C_(40)X_4碳鹵球簇型分子 ； PM3半經驗分子軌域法 ； 優選幾何結構 ； 游離能 ； 能隙 ； 生成焓 ； Gibbs能量 ； 原子化熱 ； 振動頻率 ； 1, 3, 5, 7-四鹵化金鋼烷化合物 ； C_(40) Cluster Molecule, C_(40)H_4 Cluster Molecule, C_(40)X_4 Cluster Molecule, Pm3 Semi-Empirical Molecular Orbital Method ； The Structures of Geometrical Optimization ； Ionization Potential ； Energy Gap ； Heat of Formation ； Gibbs Energy ； Atomization Energy ； Vibration Frequency ； 1,3, 5, 7- Tetrahaloadamantan Molecule.

化學

55卷2期（1997 / 06 / 01）

1 - 12

繁體中文

經本研究證實，屬於T_d點群結稱之C_(40)球簇型分子之基態為具有四個未成對電子的^5A_2開殼式組態，同時此四個未成對之價電子分別位於T_d結構的四個頂點之上。利用具單電子原子之氫原子、鹵素原子與C_(40)球簇型分子之未成對價電子鍵結將可形成穩定之C_(40)叫做氫球簇型分子及C_(40)X_4碳氫球簇型分子。本文採用Gaussian 94W程式組中之PM3半經驗分子軌域法，對此系列球簇型分子進行理論計算，獲得各球簇型分子之優選幾何結構、游離能、能隙、生成焓、Gibbs能量、原子化熱和振動頻率等數據。由此系列分子之優選後的各項計算結果，發現C_(40)H_4及C_(40)凡球簇型分子應該是穩定的分子，而其穩定性頗類似1，3，5，7-四鹵化金鋼烷化合物之穩定性。吾人推測此類球簇型分子應當是有可能被化學家們所合成之化合物。

This work demonstrates that the ground state of C_(40) cluster molecule belonging to a Td symmetry structure is a ^5A_2 open-shell configuration with four unpaired electrons. These four unpaired electrons are located at the tip points of the Td symmetry structure. This work also shows that the four unpaired electrons of C_(40) cluster molecule can easily react with single valence atom, like hydrogen and halogen atoms, to form stable C_(40)H_4 cluster molecule and C_(40)X_4 (X=F, Cl, Br, I) cluster molecules, respectively. In this study, the PM3 semiempirical molecular orbital method were adopted to calculate theoretical data of these cluster molecules, including the structures of geometrical optimization, ionization potential, energy gap, heat of formation, Gibbs energy, atomization energy, vibration frequency etc. The calculation data above confirmed that these unknown cluster molecules are stable molecules, and their stable property is similar to 1,3,5,7tetrahaloadamantan molecule. It is quite possible that they can be synthesized experimentally in the future.