First-principles study of structural stability, magnetism, and hyperfine coupling in hydrogen clusters adsorbed on graphene
First-principles study of structural stability, magnetism, and hyperfine coupling in hydrogen clusters adsorbed on graphene
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DOI：
10.1103/physrevb.82.165446
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发表时间：
2010-10-26
影响因子：
3.7
通讯作者：
Kawazoe, Yoshiyuki
中科院分区：
文献类型：
--
作者：
Ranjbar, Ahmad;Bahramy, Mohammad Saeed;Kawazoe, Yoshiyuki
使用第一性原理电子结构计算，我们研究了各种氢团簇的结构和磁性，包括氢单体，二聚体，三聚体，四聚体和六聚体吸附在石墨烯表面上。这种缺陷系统的磁行为强烈依赖于氢原子的几何构型。的结构的稳定性被证明是依赖于两个重要的因素：氢原子之间的距离和缺陷引起的磁矩之间的交换耦合的强度。对于磁性结构，电子自旋占据特定碳原子上的准定域p（z）型态。这种准定域p（z）型态的存在被证明在氢原子附近的特定碳位点产生相对较强的超精细耦合。
Using first-principles electronic-structure calculations, we studied the structural and magnetic properties of various hydrogen clusters, including hydrogen monomer, dimers, trimers, tetramers, and hexamers adsorbed on a graphene surface. The magnetic behaviors of such defective systems were shown to strongly depend on the geometrical configuration of hydrogen atoms. The stability of the structures was demonstrated to be dependent on two important factors: the distance between hydrogen atoms and the strength of exchange couplings between the defect-induced magnetic moments. For the magnetic structures, the electron spins populate the quasilocalized p(z)-type states on specific carbon atoms. The presence of such quasilocalized p(z)-type states was shown to yield relatively strong hyperfine couplings at particular carbon sites in the neighborhood of hydrogen atoms.