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Through matrix isolation infrared spectrometry and quantum chemical calculations, the reactions of laser ablated V, Nb, and Ta with boron trifluoride were investigated in excess solid neon at 4 K. The possible reaction products FBMF 2 , F 2 BMF, and BMF 3 (M = V, Nb, and Ta) were calculated at the B3LYP, BPW91, and CCSD(T) levels of theory. The B-M bond strength in FBMF 2 molecules is confirmed by energy decomposition analysis-natural orbitals for chemical valence calculations, CASSCF calculation, and natural bond orbital analysis, which favors one σ bond and two half π bonds.

By combining the particle swarm optimization algorithm with first-principles calculation, the high-pressure phase diagram of Zn-F binary compounds was established. An unexpected stoichiometry of ZnF 3 with space group Cccm is thermodynamically stable above 183 GPa. The new structure is fascinating with the appearance of Zn 2+ [F 3 ] 2- units. The stability of the new phase stems from the mixed ionic and covalent chemical bonding in ZnF 3 . The electronic properties indicate that Zn has a tendency to form high oxidation states under higher pressure. Our work is an important step in understanding the bonding behavior of Zn under extreme conditions and provides a valuable reference for experimental synthesis and identification of ZnF 3 .

Systematic americyl-hydration cations were investigated theoretically to understand the electronic structures and bonding in [(AmO 2 )(H 2 O) n ] 2+/1+ ( n = 1-6). We obtained the binding energy using density functional theory methods with scalar relativistic and spin-orbit coupling effects. The geometric structures of these species have been investigated in aqueous solution via an implicit solvation model. Computational results reveal that the complexes of five equatorial water molecules coordinated to americyl ions are the most stable due to the enhanced ionic interactions between the AmO 2 2+/1+ cation and multiple oxygen atoms as electron donors. As expected, Am-O water bonds in such series are electrostatic in nature and contain a generally decreasing covalent character when hydration number increases., Competing Interests: The authors declare no competing financial interest.

The activation of ammonia by cerium atom has been investigated in solid argon using infrared spectroscopy and density functional theoretical calculations. The results reveal that the spontaneous formation of CeNH 3 complex on annealing is the initial step in the reactions of cerium atoms with ammonia. The CeNH 3 complexes rearrange to generate the inserted HCeNH 2 molecules on irradiation. A "triplet-singlet" spin conversion occurs along the reaction path in which HCeNH 2 ( 3 A″) isomerizes into H 2 CeNH ( 1 A'). The H 2 CeNH molecules finally decompose to yield HCeN + H 2 upon photolysis. The periodic trend and differences for the M + NH 3 (M = Ti, Zr, Hf, Ce, Th) systems are discussed on the basis of the present and previous works. DFT calculations predict that the most stable ground state for HHfNH 2 and HThNH 2 is singlet due to the stronger relativistic effects in Hf and Th atoms, while that for HTiNH 2 , HZrNH 2 , and HCeNH 2 is triplet. Besides, the H 2 -elimination process is different for Ce and M (Ti, Zr, Hf, Th) cases.