TY  - JOUR
AU  - Šljivančanin, Željko
AU  - Andersen, Mie
AU  - Hornekaer, Liv
AU  - Hammer, Bjork
PY  - 2011
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/4324
AB  - The structure and stability of small hydrogen clusters adsorbed on graphene is studied by means of density functional theory (DFT) calculations. Clusters containing up to six H atoms are investigated systematically, with the clusters having either all H atoms on one side of the graphene sheet (cis-clusters) or having the H atoms on both sides in an alternating manner (trans-clusters). The most stable cis-clusters found have H atoms in ortho- and para-positions with respect to each other (two Hs on neighboring or diagonally opposite carbon positions within one carbon hexagon), while the most stable trans-clusters found have H atoms in ortho-trans-positions with respect to each other (two Hs on neighboring carbon positions, but on opposite sides of the graphene). Very stable trans-clusters with 13-22 H atoms were identified by optimizing the number of H atoms in ortho-trans-positions and thereby the number of closed, H-covered carbon hexagons. For the cis-clusters, the associative H(2) desorption was investigated. Generally, the desorption with the lowest activation energy proceeds via para-cis-dimer states, i.e., involving somewhere in the H clusters two H atoms that are positioned on opposite sites within one carbon hexagon. H(2) desorption from clusters lacking such H pairs is calculated to occur via hydrogen diffusion causing the formation of para-cis-dimer states. Studying the diffusion events showed a strong dependence of the diffusion energy barriers on the reaction energies and a general odd-even dependence on the number of H atoms in the cis-clusters.
T2  - Physical Review B: Condensed Matter and Materials Physics
T1  - Structure and stability of small H clusters on graphene
VL  - 83
IS  - 20
DO  - 10.1103/PhysRevB.83.205426
ER  - 

@article{
author = "Šljivančanin, Željko and Andersen, Mie and Hornekaer, Liv and Hammer, Bjork",
year = "2011",
abstract = "The structure and stability of small hydrogen clusters adsorbed on graphene is studied by means of density functional theory (DFT) calculations. Clusters containing up to six H atoms are investigated systematically, with the clusters having either all H atoms on one side of the graphene sheet (cis-clusters) or having the H atoms on both sides in an alternating manner (trans-clusters). The most stable cis-clusters found have H atoms in ortho- and para-positions with respect to each other (two Hs on neighboring or diagonally opposite carbon positions within one carbon hexagon), while the most stable trans-clusters found have H atoms in ortho-trans-positions with respect to each other (two Hs on neighboring carbon positions, but on opposite sides of the graphene). Very stable trans-clusters with 13-22 H atoms were identified by optimizing the number of H atoms in ortho-trans-positions and thereby the number of closed, H-covered carbon hexagons. For the cis-clusters, the associative H(2) desorption was investigated. Generally, the desorption with the lowest activation energy proceeds via para-cis-dimer states, i.e., involving somewhere in the H clusters two H atoms that are positioned on opposite sites within one carbon hexagon. H(2) desorption from clusters lacking such H pairs is calculated to occur via hydrogen diffusion causing the formation of para-cis-dimer states. Studying the diffusion events showed a strong dependence of the diffusion energy barriers on the reaction energies and a general odd-even dependence on the number of H atoms in the cis-clusters.",
journal = "Physical Review B: Condensed Matter and Materials Physics",
title = "Structure and stability of small H clusters on graphene",
volume = "83",
number = "20",
doi = "10.1103/PhysRevB.83.205426"
}

Šljivančanin, Ž., Andersen, M., Hornekaer, L.,& Hammer, B.. (2011). Structure and stability of small H clusters on graphene. in Physical Review B: Condensed Matter and Materials Physics, 83(20).
https://doi.org/10.1103/PhysRevB.83.205426

Šljivančanin Ž, Andersen M, Hornekaer L, Hammer B. Structure and stability of small H clusters on graphene. in Physical Review B: Condensed Matter and Materials Physics. 2011;83(20).
doi:10.1103/PhysRevB.83.205426 .

Šljivančanin, Željko, Andersen, Mie, Hornekaer, Liv, Hammer, Bjork, "Structure and stability of small H clusters on graphene" in Physical Review B: Condensed Matter and Materials Physics, 83, no. 20 (2011),
https://doi.org/10.1103/PhysRevB.83.205426 . .