Insights on the structural and electronic properties of ScC n + , YC n + , LaC n + (n = 3–6) systems

Osorio, Edison; Ferraro, Franklin; Hadad, C. Z.; Rabanal‐León, Walter A.; Tiznado, William

doi:10.1007/s00214-016-1976-8

Cited by 2 publications

(1 citation statement)

References 69 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The molecular graph for the initial activated ABAu 4 species (see Appendix 6 in the Supporting Information), within the QTAIM framework, shows the presence of a bond path for the Au4H10 interaction, but not for the Au4B9 interaction. However, as we have reported in another case, there is a pronounced curvature of the bond paths toward the Au4B9 internuclear region, which denote certain degree of AuB interaction via other atoms (multicenter interactions). In fact, second‐order perturbation theory analysis of Fock matrix within the NBO scheme predicts an interaction between the B9H10 bonding localized orbital (donor) and the Au4Au3 antibonding localized orbital (acceptor).…”

Section: Resultssupporting

confidence: 72%

Activation and diffusion of ammonia borane hydrogen on gold tetramers

Mejía

Ferraro

Osorio

et al. 2017

Int J of Quantum Chemistry

Self Cite

View full text Add to dashboard Cite

One of the most serious candidates for safe storage of high hydrogen densities is ammonia borane, AB. Likewise, one of the most versatile catalysts known is gold in the form of atomic clusters. Taking these elements into account, in this work a density functional theory -based study about initial activation, detachment, and diffusion of ammonia borane hydrogen on gold tetramer, as a catalyst model, is developed. It was found that the total process is exergonic and that the hydrogen diffusion occurs with very low energy barriers. The process has a hydrogen detachment energy barrier lower than the one of the uncatalyzed AB, and that is easily overcome by the energy expelled in the previous stage of formation of the initial activated species. Additionally, all the process is assisted by the fluxionality of the gold cluster, and occurs via a unique catalytically activated initial species, which contains a three-center simultaneous interaction at the catalytically activated zone.ammonia borane, gold cluster catalyst, gold-fluxionality, theoretical study, three-center bonding | I N TR ODU C TI ONResearch about new ways for practical, safe, and economically convenient storage and release of large quantities of hydrogen in small volumes is today a very important issue. [1,2] Hydrogen has an energy content by mass almost three times superior to petroleum, [3] is the most abundant substance in the universe, is source-independent, and its combustion product, water, is environmentally friendly. Additionally, the availability of activated hydrogen is highly relevant for a large number of reactions in the chemical industry, where reduction or hydrogenation are necessary steps. [4,5] Among lightweight hydrogen storage materials, ammonia borane, AB (H 3 BNH 3 ), is a substance that contains large amounts of hydrogen (a total of 19.6 wt.%), [3] which is relatively easy to extract, either by direct or by assisted thermolysis, [6,7] by catalyzed room temperature solvolysis, [3,[8][9][10][11] or by other methods. [12][13][14][15] Additionally, AB can be easily and safely transported, [16] because, on the one hand, is a relatively stable solid at room conditions, [3,6,16] and is a substance soluble in many solvents, such as water, methanol, and tetraglyme. [3,[8][9][10][11][12] It has been found that the use of transition metals as catalysts in the AB dehydrogenation has the advantage of avoiding the expenditure of large amounts of energy, necessary for the hydrogen release. [7,[16][17][18] Even, in some cases, the catalysis has emerged as a solution to diminish the unwanted by-products of hydrogen release. [10,12,18] Transition metals of different nature, both noble and non-noble, as well as binary or tertiary combinations among them, have shown catalytic activity toward the extraction of hydrogen from AB. [3,[8][9][10][11][12]17,18] In the case of nanoparticles, the studies show that although some transition metals are better than others, the decrease in size (within certain limits and conditions [19] ) of the nanoparticles of the ...

show abstract

Section: Resultssupporting

confidence: 72%