Project/Area Number |
02453020
|
Research Category |
Grant-in-Aid for General Scientific Research (B)
|
Allocation Type | Single-year Grants |
Research Field |
有機化学一般
|
Research Institution | Yokohama National University |
Principal Investigator |
NAGASE Shigeru Yokohama National Univ., Chemistry, Professor, 教育学部, 教授 (30134901)
|
Co-Investigator(Kenkyū-buntansha) |
KUDO Takako Gunma Univ., Chemistry, Assistant Professor, 教養部, 講師 (10137911)
|
Project Period (FY) |
1990 – 1991
|
Project Status |
Completed (Fiscal Year 1991)
|
Budget Amount *help |
¥5,100,000 (Direct Cost: ¥5,100,000)
Fiscal Year 1991: ¥800,000 (Direct Cost: ¥800,000)
Fiscal Year 1990: ¥4,300,000 (Direct Cost: ¥4,300,000)
|
Keywords | Heavier group 14 atoms / Heavier group 15 atoms / Unsaturated compounds / Polycyclic compounds / Molecular design / 高周期典型元素 / 反応制御 |
Research Abstract |
We have carried out ab initio calculations of the compounds whose skeletons are made of the heavier main group 14 (Si, Ge, Sn, and Pb) and group 14 (P, As, Sb, and Bi) atoms in the expectation of novel properties which carbon compounds do not have. A primary concern is to characterize the heavier atom skeletons compared with carbon skeletons and predict a general rule which is useful in the design of new material. Doubly Bonded Compounds. The atoms in group 14 are incapable of forming double bonds as they become heavier because of a lower tendency to form hybrid orbitals. In contrast, the tendency of the heavier group 15 atoms is not especially unfavorable in forming double bonds. Aromatic and Antiaromatic Compounds. Concepts such as aromaticity and antiaromaticity established in carbon chemistry are of limited value when they are applied to the heavier analogues of benzene and cyclobutadiene. Substituents play a important role in designing aromatic or antiaromatic compounds. Polycyclic Compounds. The strain energies of polycyclic carbon compounds are greatly decreased when the skeletal carbons are replaced by the heavier atoms. This property is noteworthy since it is useful for designing less strained polycyclic cage compounds. Unusually Short Phantom Bonds. Several interesting properties of bonding between the heavier atoms are suggested which is not seen in carbon chemistry.
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