The geometry optimizations and evaluation of electronic properties of prism carbon series were performed based on the density functional theory using plane waves with the PBE functional. The most stable structure was a prism-C₅ tube. Since the band gaps of these carbon tubes, as estimated by band structure calculations ranged from zero to 0.96 eV, it is considered that the electronic characteristics change from semi-conductive to metallic with increasing number of carbon atoms per unit cell. Since the activation energies of prism-C₄ and -C₆ tubes are larger than the thermal energy, estimated from k_BT, these structures can exist at ambient temperatures.

中文翻译：

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利用平面波的密度泛函理论优化棱镜碳管的几何形状并评估其电子性能

基于密度泛函理论，使用具有PBE功能的平面波，对棱镜碳系列进行了几何优化和电子性能评估。最稳定的结构是棱镜C ₅管。由于这些碳管的带隙（通过能带结构计算所估计）在0到0.96 eV的范围内，因此可以认为，随着每晶胞碳原子数的增加，电子特性从半导体变为金属。由于棱镜-C ₄和-C _6的管的活化能大于热能（根据k _B T估算），因此这些结构可以存在于环境温度下。