A combination of infrared multiple photon dissociation (IRMPD) spectroscopy and density functional theory calculations is used to investigate the structures and charge-transfer properties of clusters containing transition metals (TM = Co(II), Ni(II), Cu(I), Zn(II), Rh(III), Pd(II), Ag(I), Cd(II)) and the dodecafluorododecaboron dianion, B12F12(2-). In all cases, IRMPD resulted in transfer of electron density to the metal center and production of B12F12(-). Metals that exhibit the highest degree of charge transfer are found to induce reaction among the B12F12 cages, leading to production of BnFm (up to n = m = 24).

Free energy calculations are a crucial part of understanding chemical systems but are often computationally expensive for all but the simplest of systems. Various enhanced sampling techniques have been developed to improve the efficiency of these calculations in numerical simulations. However, the majority of these approaches have been applied using classical molecular dynamics. There are many situations where nuclear quantum effects impact the system of interest and a classical description fails to capture these details. In this work, path integral molecular dynamics has been used in conjunction with umbrella sampling, and it has been observed that correct results are only obtained when the umbrella sampling potential is applied to a single path integral bead post quantization. This method has been validated against a Lennard-Jones benchmark system before being applied to the more complicated water dimer system over a broad range of temperatures. Free energy profiles are obtained, and these are utilized in the calculation of the second virial coefficient as well as the change in free energy from the separated water monomers to the dimer. Comparisons to experimental and ground state calculation values from the literature are made for the second virial coefficient at higher temperature and the dissociation energy of the dimer in the ground state.

We report a new fast ion-conducting lithium thioborate halide, Li 6 B 7 S 13 I, that crystallizes in either a cubic or tetragonal thioboracite structure, which is unprecedented in boron−sulfur chemistry. The cubic phase exhibits a perovskite topology and an argyrodite-like lithium substructure that leads to superionic conduction with a theoretical Li-ion conductivity of 5.2 mS cm −1 calculated from ab initio molecular dynamics (AIMD). Combined single-crystal X-ray diffraction, neutron powder diffraction, and AIMD simulations elucidate the Li + -ion conduction pathways through 3D intra-and intercage connections and Li-ion site disorder, which are all essential for high lithium mobility. Furthermore, we demonstrate that Li + ordering in the tetragonal polymorph impedes lithium-ion conduction, thus highlighting the importance of the lithium substructure and lattice symmetry in dictating transport properties.

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Many children suffering from autism spectrum disorder (ASD) experience gastrointestinal (GI) conditions. Enterocloster bolteae has been regularly detected in the stool of individuals suffering from GI symptoms and autism. Literature...