Structure and Electronic State of Carbolite

研究表明，新的一维碳晶体"cabolite"沿其链向具有长的沿着周期性，但迄今为止还没有建立起具有扭结的一维碳链的稳定结构。本研究计划的目的是寻找碳链的稳定结构及其电子态，主要结果如下：（1）纯一维碳链没有扭结结构，只有直链结构的累积多烯和多烯是稳定的，（2）几种组合碳链具有稳定的扭结结构，沿其链向沿着具有长的周期性，表明碳硼石与碳炔一样可能具有碳链的网状结构，（3）加氢碳链在加氢碳位上具有扭结结构，（4）当相邻扭结之间存在偶数个碳原子时，碳链具有稳定的结构，并成为非磁性半导体，（5）当碳原子数为奇数时，碳链为反铁磁态，结构不稳定;（6）碳硼石可能是碳链加氢的聚集体，这与碳硼石的密度比另一种一维碳晶体"卡宾"低得多的事实相一致。碳质岩的结构至今无法确定，反映了其实验研究的不足，因此，对碳质岩的实验结构分析进行新的研究是十分必要的。

It has been demonstrated that the new one-dimensional carbon crystal' cabolite' has a long periodicity along its chain direction, but no stable structure has been established for the one-dimensional carbon chains with kinks up to the present. The purposes of this research project are the search of stable structures of carbon chains and the investigation of their electronic states.The main results are the followings : (1) the purely one-dimensional carbon chain has no kinked structure and only the cumulene and polyene with straight chain structures are stable, (2) several combined carbon chains have stable kinked structures and a long periodicity along their chain direction, indicating the possibility that carbolite as well as carbyne take the network structure of carbon chains, (3) the carbon chains with added hydrogen have the kinked structure at the carbon position with added hydrogen, (4) in the case that even numbers of carbon atoms exist between the adjacent kinks, the carbon chains have stable structures and bacome non-magnetic semiconductors, (5) in the case that the number of carbon atoms is odd, the carbon chains are antiferromagnetic state with less stable structures, and (6) carbolite might be an aggregate of carbon chains with added hydrogen, in accord with the fact that the density of carbolite is considerably low compaired with another one-dimensional carbon crystal' carbyne'.At present, the definite structure of carbolite cannot be determined, reflecting its poor experimental studies, so that the new investigations of experimental structure analisis are strongly expected.