On the C60 carbyne links (from 2 12 to 6 32)

• Published in: International journal of quantum chemistry Vol. 75; no. 4-5; pp. 839 - 846
• Main Authors: Dobrowolski, Jan Cz, Mazurek, Aleksander P.
• Format: Journal Article
• Language: English
• Published: New York John Wiley & Sons, Inc 1999
• Subjects: ab initio; alysidamer; carbyne; catenamer; catenanes; links; topological isomerism
• ISSN: 0020-7608; 1097-461X
• DOI: 10.1002/(SICI)1097-461X(1999)75:4/5<839::AID-QUA49>3.0.CO;2-9

The structure and stability of catecarbynes, i.e., nonlinear C60 carbynes of the link (catenane) type, have been established by ab initio calculations. For each C60 catecarbyne topological type examined, the energy changes evaluated with the components size varying in the series (C60−2nC2n), where 20≥n≥5, which exhibit one to several minima, have been shown to depend on the number of crossings and structure type. For the 2 12C60 catecarbyne, the lowest structure is built from two cyclic carbynes of the same size but, for the 4 12C60 catecarbyne, the two minimum energy structures are those composed of the C24 and C36 cycles and the 4 12C30C30 molecule is the local maximum structure. For the 5 12C60 catecarbyne, the minimum energy structure is constructed from the C20 and C40 cycles and the local maximum structure is formed when the first and the second cycles have 42 and 18 C atoms, respectively. The six‐crossings catecarbynes (6 12, 6 22, and 6 32) exhibit an even more complex behavior. Such relationships show that, for the same topological catenane type with several crossings, some structures may be more stable by several hundreds of kilocalories/mole than others. ©1999 John Wiley & Sons, Inc. Int J Quant Chem 75: 839–846, 1999