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The unique reactivity of the acetylenic unit in DMSO gives rise to ubiquitous synthetic methods. We theoretically consider CaC2 solubility and protolysis in DMSO and formulate a strategy for CaC2 activation in solution-phase chemical transformations. For this, we use a new strategy for the modeling of ionic compounds in strongly coordinating solvents combining Born–Oppenheimer molecular dynamics with the DFTB3-D3(BJ) Hamiltonian and static DFT computations at the PBE0-D3(BJ)/pob-TZVP-gCP level. We modeled the thermodynamics of CaC2 protolysis under ambient conditions, taking into account its known heterogeneity and considering three polymorphs of CaC2. We give a theoretical basis for the existence of the elusive intermediate HC Created by potrace 1.16, written by Peter Selinger 2001-2019 C–Ca–OH and show that CaC2 insolubility in DMSO is of thermodynamic nature. We confirm the unique role of water and specific properties of DMSO in CaC2 activation and explain how the activation is realized. The proposed strategy for the utilization of CaC2 in sustainable organic synthesis is outlined., Constructing the carbon framework from a carbon-neutral source: a new computational model for ionic pairs in solution based on DFTB MD and DFT helps to propose a strategy for sustainable organic transformations with solid CaC2.

We used hybrid density functional theory to investigate 50% cubic solid solutions based on Fe-doped LaGaO3 and LaAlO3. The supercell composed of 8 primitive cells was used. All the possible configu...

Scandium molybdate is the first obtained stable material with negative coefficient of thermal expansion. An anisotropic thermal expansion occurs as the result of a decrease in the sizes along two axes at the expense of rotation of polyhedral parts and an increase along the third axis. For scandium molybdate thermodynamically stable are monoclinic phase in the region of low temperatures and orthorhombic phase in the region of high temperatures. In general the formation enthalpy of monoclinic phase is lower than of the orthorhombic phase; however, the orthorhombic phase is preferable from the point of view of entropy. In the case of the formation of a two-phase system, the question arises about the distribution of scandium and gadolinium atoms over these phases. The paramagnetic component of magnetic susceptibility obeys the Curie–Weiss law over the whole temperature range and for all the concentrations.

Calculations of the cubic models of two solid solutions LaGa0.5Fe0.5O3 and LaAl0.5Fe0.5O3 have been performed within the hybrid density functional theory. Multiple configurations have been considered for the solid solutions resulting from a different distribution of Fe atoms over the p-metal (Ga or Al) positions accounting for different spin orientation for Fe atoms themselves. It was demonstrated that 27 structures for both LaGa0.5Fe0.5O3 and LaAl0.5Fe0.5O3 should be treated to account for all the possible configurations in case of cubic 2 × 2 × 2 supercell. Optimized geometry, energy, and electron properties were calculated for all the obtained configurations. Statistical weights and probabilities were estimated for each symmetry non-equivalent configuration of the solid solutions within the canonical ensemble. A new parameterization for the dilute Ising model has been proposed. In this model, we account for non-magnetic contributions, which are absent in the simple Ising model, using the lattice approach based on the concept of interchange energy. Two model parameters (the magnetic coupling constant and interchange energy) were fitted to the calculated total energies of all considered configurations of both solid solutions. The dilute Ising model confirmed the benefit of Fe-clustering in doped lanthanum gallate against aluminate. Different signs of the estimated interchange energy enable us to explain the reasons for such differences.