In this work, we apply the recently proposed MP2 correction to incremental energies within the domain-specific basis set approach to incrementally expanded CCSD(T)(F12) energies. The approach is tested for a set of 27 molecules with different electronic structures including water clusters, aqua complexes, aliphatic hydrocarbons, alkenes, alkynes, aromatic systems, and amino acids. The root mean squared deviation of the absolute energies with respect to the standard calculation is 1.7 kJ/mol, the mean absolute deviation is 1.2 kJ/mol, and the range is 4.7 kJ/mol. The wall time of the computations is reduced due to the application of a doubly parallel strategy-the independent coupled cluster calculations are performed on up to 70 nodes in parallel, and in addition the computations on one node are performed with the SMP-parallelized coupled cluster code in TURBOMOLE. Using this strategy, we can perform computations in minutes or hours, instead of days or months. Applying the proposed scheme enables us to routinely treat systems with 50 atoms at the CCSD(T)(F12) level in combination with appropriate basis sets to obtain nearly CBS accuracy. Also, larger systems are still feasible on a standard cluster as demonstrated for H3O(+)(H2O)25Cl(-) with 80 atoms.

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Among the candidate cathode materials for sodium-ion batteries (SIBs), NaxMnO2 (NMO) layered oxides are especially attractive in terms of working potential (ca. 3.0 V vs. Na+/Na) and high initial specific charge.

A method for the preparation of a variety of cyclobutanes via 4-exo cyclization of radicals is presented. Radical generation is carried out by electron transfer from titanocene(III) chlorides to epoxides. The reaction relies on the acceleration of the cyclization through the use of alpha,beta-unsaturated carbonyl compounds as radical traps and the thermodynamic stabilization of the cyclobutylcarbinyl radicals through conjugation. The mechanism of the transformation was investigated by a combined theoretical and experimental study. The computational results provide the crucial energetic and structural features of pertinent intermediates and transition structures. Moreover, the origins of the diastereoselectivity of the 4-exo cyclization are outlined for the first time. Catalysts for those cases where "Cp2TiCl" did not perform in a satisfactory manner have been devised. Through the introduction of tert-butyl or cyclo-hexyl substituted cyclopentadienyl ligands the longevity of the pivotal beta-titanoxy radicals is increased sufficiently enough to enable the slow but often surprisingly diastereoselective formation of the cyclobutylcarbinyl radical. The resulting transformation constitutes the first general approach to cyclobutanes using radical chemistry.

Aging reduced the translucency in all specimens tested. Furthermore, translucency differed between the zirconia brands tested. Nevertheless, the differences were below the detectability threshold of the human eye. The aging process can influence the translucency and thus the esthetic outcome of zirconia restorations; however, the changes in translucency were minimal and probably undetectable by the human eye.