Preparation of triclinic alite with short soakings in a small experimental high-temperature furnace

The article deals with a laboratory preparation of triclinic modification of clinker mineral tricalcium silicate. A substantial part of the article is devoted to the technology and technique of firing a sample of tricalcium silicate, which would in the future allow the study of the development of the crystal lattice structure of this clinker mineral at short isothermal durations, in the order of minutes. As part of the research, a small high-temperature experimental furnace was designed and constructed. Based on the results, we can express the suitability and applicability of this furnace for the study of the formation of triclinic tricalcium silicate at short soakings.

Lithium-Cation Conductivity of Solid Solutions in Li6-xZr2-xAxO7 (A = Nb, Ta) Systems

Li6-xZr2-xAxO7 (A = Nb; Ta) system with 0 < x < 0.30 is synthesized by glycine-nitrate method. Boundaries of solid solutions based on monoclinic Li6Zr2O7 are determined; temperature (200–600 °C) and concentration dependences of conductivity are investigated. It is shown that monoclinic Li6Zr2O7 exhibits better transport properties compared to its triclinic modification. Li5.8Zr1.8Nb(Ta)0.2O7 solid solutions have a higher lithium-cation conductivity at 300 °C compared to solid electrolytes based on other lithium zirconates due the “open” structure of monoclinic Li6Zr2O7 and a high solubility of the doping cations.

A monoclinic modification of (4Z)-1-benzyl-4-(2-oxopropylidene)-2,3,4,5-tetrahydro-1H-1,5-benzodiazepin-2-one

In the title molecule, C19H18N2O2, the orientation of the oxopropylidene substituent is largely determined by an intramolecular N—H...O hydrogen bond. In the crystal, C—H...O hydrogen bonds form zigzag chains, which are elaborated into sheets lying parallel to (101) by complementary C—H...π interactions. Comparisons to the structure of the triclinic modification are made.

Crystal structure of the triclinic modification of 1-methyl-4-nitroimidzole, C4H5N3O2

C4H5N3O2, triclinic, P1 (no. 1), a = 3.8976(6) Å, b = 5.7235(8) Å, c = 6.2670(10) Å, α = 89.630(12)°, β = 84.800(13)°, γ = 76.970(13)°, V = 135.63(4) Å3, Z = 1, Rgt(F) = 0.0519, wRref(F2) = 0.1303, T = 104.8 K.

Triclinic modification of diaquabis(5-carboxy-1H-imidazole-4-carboxylato-κ2N3,O4)iron(II)

The title compound, [Fe(C5H3N2O4)2(H2O)2], is a triclinic modification of a monoclinic form recently reported by Duet al.[Acta Cryst.(2011), E67, m997]. The FeIIion lies at an inversion center and is coordinated by two N and two O atoms from two 5-carboxy-1H-imidazole-4-carboxylate ligands intranspositions, together with two water molecules, completing a slightly distorted octahedral coordination. Intermolecular N—H...O hydrogen bonding between the N—H group of the imidazole ring and the deprotonated carboxylate group builds a chain of 5-carboxy-1H-imidazole-4-carboxylate anions along the [101] direction. The water molecules form intermolecular hydrogen bonds to O—C and O=C sites of the carboxylate group in adjacent layers.