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HBr is Halite, Rock Salt structured and crystallizes in the cubic Fm-3m space group. The structure is zero-dimensional and consists of four hydrobromic acid molecules and four hydrogen molecules.
SnH4 crystallizes in the monoclinic P2_1/m space group. The structure is zero-dimensional and consists of two 7440-31-5 molecules and four hydrogen molecules.
(Ba)6H2 is Uranium Silicide-like structured and crystallizes in the hexagonal P6_3/mmc space group. The structure is zero-dimensional and consists of six barium molecules and two hydrogen molecules.
GeH4 is alpha carbon monoxide-like structured and crystallizes in the orthorhombic Cmcm space group. The structure is zero-dimensional and consists of four germanium molecules and eight hydrogen molecules.
BNH2H2 is Cyanogen Chloride-like structured and crystallizes in the orthorhombic Pmn2_1 space group. The structure is zero-dimensional and consists of two boranamine molecules and two hydrogen molecules.
AlH6 is Cyanogen Chloride-derived structured and crystallizes in the monoclinic C2/c space group. The structure is zero-dimensional and consists of four $l^{2}-alumane molecules and twelve hydrogen molecules.
(N2)2(CO2)4H2 is Cyanogen Chloride-derived structured and crystallizes in the orthorhombic P2_12_12 space group. The structure is zero-dimensional and consists of four ammonia molecules, four carbon dioxide molecules, and two hydrogen molecules.
(Eu)6H2 crystallizes in the hexagonal P6_3/mmc space group. The structure is zero-dimensional and consists of six europium molecules and two hydrogen molecules.
SnH4 crystallizes in the orthorhombic Cmcm space group. The structure is zero-dimensional and consists of four 7440-31-5 molecules and eight hydrogen molecules.
Accelerating the discovery of new molecules with targeted properties is a central challenge in molecular design. In this contribution, we present an AI-driven molecular discovery framework that integrates Large Language Models (LLMs) for generative molecular design with Machine Learning (ML)-based screening to identify novel Liquid Organic Hydrogen Carrier (LOHC) candidates. Using the developed framework, LOHC molecules were systematically generated, evaluated, and refined iteratively, combining LLM-guided molecular generation and ML-predicted hydrogenation enthalpies (Δ H ), under physicochemical property constraints such as optimal melting points (MP), desired hydrogen storage capacity (wt% H 2 ), and synthetic accessibility (SA) scores. This approach enabled the discovery of 42 new LOHC candidates in two distinct campaigns, one seeded with experimentally known and another with previously computationally identified LOHCs, respectively. Although we began with different numbers of starting molecules (31 vs . 7 seed molecules), both runs yielded a comparable number of viable candidates, suggesting an influence of chemically intuitive seed molecule selection for success. Selected LOHC molecules, such as 3-methyl pyridine, 1-ethylnapthalene, 1,1-diphenylethane, and benzofuran, were experimentally tested and compared with benchmark LOHCs (toluene and 9-ethylcarbazole) for hydrogenation using a series of commercial supported metal catalysts. The order of conversion into fully hydrogenated products at 200 °C was 3-methyl pyridine (100%) > 9-ethyl carbazole (86.4%) > 2,3-benzofuran (74%) > 1,1-diphenylethane (66.9%) > 1-ethylnapthalene (66.7%) > toluene (57%), further validating the AI-guided molecular design. This study demonstrates promise of LLM-driven molecular design in conjunction with ML-based screening for accelerated discovery and design of molecules.
Density functional theory (DFT) is a valuable tool for calculating adsorption energies toward designing materials for hydrogen storage. However, dispersion forces being absent from the local/semi-local theory, it remains unclear as to how the consideration of van der Waals (vdW) interactions affects such calculations. For the first time, we applied diffusion Monte Carlo (DMC) to evaluate the adsorption characteristics of a hydrogen molecule on a (5,5) armchair silicon-carbide nanotube (H 2 -SiCNT). Within the DFT framework, we benchmarked various exchange-correlation functionals, including those recently developed for treating dispersion or vdW interactions. We found that the vdW-corrected DFT methods agree well with DMC, whereas the local (semilocal) functional significantly over (under)-binds. Furthermore, we fully optimized the H 2 -SiCNT geometry within the DFT framework and investigated the correlation between the structure and charge density. The vdW contribution to the adsorption was found to be non-negligible at similar to 1 kcal/mol per hydrogen molecule, which amounts to 9-29% of the ideal adsorption energy required for hydrogen storage applications.
Perdew-Zunger self-interaction correction (PZ-SIC) offers a route to remove self interaction errors on an orbital-by-orbital basis. A recent formulation of PZ-SIC by Pederson, Ruzsinszky and Perdew proposes restricting the unitary transformation to localized orbitals called Fermi-Löwdin orbitals. This formulation, called the FLOSIC method, simplifies PZ-SIC calculations and was implemented self-consistently using a Jacobi-like (FLOSIC-Jacobi) iteration scheme. In this work we implement the FLOSIC approach using the Krieger-Li-Iafrate (KLI) approximation to the optimized effective potential (OEP). We compare the results of present FLOSIC-KLI approach with FLOSIC-Jacobi scheme for atomic energies, atomization energies, ionization energies, barrier heights, polarizability of chains of hydrogen molecules etc. to validate the FLOSIC-KLI approach. The FLOSICKLI approach, which is within the realm of Kohn-Sham theory, predicts smaller energy gaps between frontier orbitals due to the lowering of eigenvalues of the lowest unoccupied orbitals. Results show that atomic energies, atomization energies, ionization energy as an absolute of highest occupied orbital eigenvalue, and polarizability of chains of hydrogen molecules between the two methods agree within 2%. Lastly the FLOSIC-KLI approach is used to determine the vertical ionization energies of water clusters.
We investigate switching of photoluminescence from PbS quantum dots crosslinked with photochromic diarylethene molecules with different degree of halogenation.
Ni(H2O)6(BH)12(H2)6(O2)3 crystallizes in the cubic F4_132 space group. The structure is zero-dimensional and consists of ninety-six boranediylradical molecules, forty-eight hydrogen molecules, eight nsvfpfuroxfzjs-uhfffaoysa-n molecules, and sixteen trioxirane molecules.
H2S2O7 crystallizes in the monoclinic C2/c space group. The structure is zero-dimensional and consists of four disulfuric acid molecules, four hydrogen peroxide molecules, four sulfino hydrogen sulfite molecules, and four H2S2O7 clusters. In each H2S2O7 cluster, there are two inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 1.00 Å. In the second H1+ site, H1+ is bonded in a distorted single-bond geometry to two O2- atoms. There is one shorter (1.01 Å) and one longer (1.66 Å) H–O bond length. There are two inequivalent S6+ sites. In the first S6+ site, S6+ is bonded to four O2- atoms to form corner-sharing SO4 tetrahedra. There are a spread of S–O bond distances ranging from 1.43–1.69 Å. In the second S6+ site, S6+ is bonded to four O2- atoms to form corner-sharing SO4 tetrahedra. There are a spread of S–O bond distances ranging from 1.42–1.63 Å. There are seven inequivalent O2- sites. In the first O2- site, O2- is bonded in a bent 120 degrees geometry to two S6+ atoms. In the second O2- site, O2- is bonded in a single-bond geometry to one S6+ atom. In the third O2- site, O2- is bonded in a single-bond geometry to one S6+ atom. In the fourth O2- site, O2- is bonded in a bent 120 degrees geometry to one H1+ and one S6+ atom. In the fifth O2- site, O2- is bonded in a 2-coordinate geometry to one H1+ and one S6+ atom. In the sixth O2- site, O2- is bonded in a bent 120 degrees geometry to one H1+ and one S6+ atom. In the seventh O2- site, O2- is bonded in a single-bond geometry to one S6+ atom.
CaSn(S)3 crystallizes in the monoclinic C2 space group. The structure is zero-dimensional and consists of four 7440-31-5 molecules, four calcium molecules, four hydrogen disulfide molecules, and four hydrogen sulfide molecules.
Al(H2)6 is alpha carbon monoxide-like structured and crystallizes in the cubic Fd-3m space group. The structure is zero-dimensional and consists of eight aluminum molecules and forty-eight hydrogen molecules.
N2SS2O5 crystallizes in the monoclinic P2_1/c space group. The structure is zero-dimensional and consists of eight ammonia molecules, four hydrogen sulfide molecules, and four sulfino hydrogen sulfite molecules.