Lattice dynamics of BC2N.
Lattice dynamics of BC2N.
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DOI：
10.1103/physrevb.53.14161
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发表时间：
1996-06
期刊：
影响因子：
--
通讯作者：
Nozaki;Itoh
中科院分区：
文献类型：
--
作者：
Nozaki;Itoh
层状材料B${\ mathm {C}}_{2}$N具有依赖于原子排列的巨大多晶结构。为了研究单层B${\ mathm {C}}_{2}$N体系的振动性质与其层内原子排列之间的关系，基于广义价力场模型计算了各种多晶结构的晶格振动，该模型的力常数由从头算总能量计算确定。得到声子态密度谱、声子色散关系和振动模式，并进行了详细的讨论。对于具有均匀原子排列的B${\ mathm {C}}_{2}$N体系，其高频振动模式受局域原子排列的敏感影响，并在声子谱中给出不同的峰结构。而对于B${\ maththrm {C}}_{2}$N系统，如果每个分离区域包含数十个以上的原子，则它们的声子谱可以用石墨和六方氮化硼谱的叠加来描述。对B${\ mathm {C}}_{2}$N晶格振动的分析有可能导致其多晶结构的确定。
A layered material, B${\mathrm{C}}_{2}$N, has huge polymorphic structures which depend on the atomic arrangements. In order to investigate the relation between the vibrational properties of monolayer B${\mathrm{C}}_{2}$N systems and their intralayer atomic arrangements, the lattice vibrations of various polymorphic structures are calculated based on a generalized valence-force field model whose force constants have been determined from ab initio total energy calculations. The obtained phonon density-of-states spectra, phonon dispersion relations, and vibrational modes are presented and discussed in detail. As for B${\mathrm{C}}_{2}$N systems with homogeneous atomic arrangements, their vibrational modes with higher frequencies are sensitively influenced by local atomic arrangements, and give different peak structures in the phonon spectra. In contrast, as for B${\mathrm{C}}_{2}$N systems with patterns segregated into graphitelike and hexagonal boron nitridelike regions, if each segregated domain contains more than dozens of atoms, their phonon spectra can be described by a superposition of the spectra of graphite and hexagonal boron nitride. The analysis of the lattice vibrations of B${\mathrm{C}}_{2}$N has a possibility of leading to the determination of its polymorphic structures.