title: Impact of position and number of boron atom substitution on hydrogen uptake capacity of Li-decorated pentalene.
abstract: We have performed an ab initio and density functional theory study of the hydrogen adsorption on a lithium (Li)-decorated pentalene (C8H6Li2) complex. The C8H6Li2complex can interact with a maximum of two hydrogen molecules with a H2uptake capacity of 3.36 wt%. The effect of the number and position of boron atom substitution in the C8H6Li2complex on the H2uptake capacity is also studied. Two and four carbon atoms are substituted by boron atoms in the C8H6Li2complex. Two different structures are considered for each of the two and four boron atom substitutions. It is found that boron substitution in the C8H6Li2complex enhances the binding energy of Li to the substrate. Four boron atom substitution at different positions also affects the H2uptake capacity. The two structures of two boron-substituted complexes (C6B2H6Li2) show the same H2uptake capacity viz. 6.63 wt%. Unlike the two boron-substituted complexes, two different structures of the four boron-substituted complexes (C4B4H6Li2) show different H2uptake capacity which is found to be 9.81 wt% and 6.76 wt%. The temperature and pressure range for energetically favourable H2adsorption on these complexes is predicted using the Gibbs free energy corrected H2adsorption energy. Various interaction energies are calculated for all the maximum H2-adsorbed complexes using the many-body analysis approach. The H2desorption temperature for these complexes is predicted using the Van't Hoff equation and is found to be in the range of 25 K to 115 K. Molecular dynamics simulations for all these complexes are performed which show that these complexes can not bind a single H2molecule at ambient conditions during the simulations. However, H2adsorption on these complexes is energetically favourable at low temperature.
authors.affiliation: Department of Physics, The Institute of Science, Fort, Mumbai 400 032, Maharashtra, India. ajaychau5@yahoo.com.
authors.forename: Priyanka
authors.initials: P
authors.lastname: Tavhare
authors.affiliation: Institute of Atomic and Molecular Sciences, Molecular Science and Technology Program, Taiwan International Graduate Program, Academia Sinica, Taipei 11529, Taiwan and Department of Physics, National Central University, Jung-Li 32001, Taiwan.
authors.forename: Amol
authors.initials: A
authors.lastname: Deshmukh
authors.affiliation: Department of Physics, The Institute of Science, Fort, Mumbai 400 032, Maharashtra, India. ajaychau5@yahoo.com.
authors.forename: Ajay
authors.initials: A
authors.lastname: Chaudhari