Recently, we reported the first monoclinic [Kuai & Cheng (2011). Acta Cryst., E67, o2787] and the ortho-rhom-bic polymorph [Kuai & Cheng (2011). Acta Cryst., E67, o3014] of the title compound, C(15)H(12)N(2)O(2). Another monoclinic polymorph was obtained accidentally by the hydro-thermal reaction of the title compound with manganese chloride in the presence of potassium hydroxide at 413 K. The ...

The ®rst of the title compounds, C31H27NO4S, (V), crystallizes in the monoclinic space group P21/c with two independent molecules in the asymmetric unit, while the second, C23H27Cl2NS, (IX), crystallizes in the orthorhombic space group Pbca with one molecule in the asymmetric unit. In both crystal structures, the 1,3-thiazolidine ring adopts a half-chair conformation. The crystal structures are...

The title compound, C15H17NO4, containing two mol-ecules in the asymmetric unit is a polymorph of the crystal structure published by Martínez et al. [(2011). Eur. J. Org. Chem. pp. 3137-3145] which at 120 K is monoclinic with one mol-ecule in the asymmetric unit. Both mol-ecules in the title compound are in the trans form. In the crystal, N-H⋯O and O-H⋯O hydrogen bonds connect mol-ecules, formi...

A new 122-type phase, monoclinic BaIr₂Ge₂ is successfully synthesized by arc melting; X-ray diffraction and scanning electron microscopy are used to purify the phase and determine its crystal structure. BaIr₂Ge₂ adopts a clathrate-like channel framework structure of the monoclinic BaRh₂Si₂-type, with space group P2₁/c. Structural comparisons of clathrate, ThCr₂Si₂, CaBe₂Ge₂, and BaRh₂Si2 struct...

Experimental and theoretical studies of the ferroelastic domain structure of the (NH 4) 3 H(SeO 4) 2 crystal in phases III and IV are performed. Using the refined structural data the orientations of Wand W 0-type domain walls, as well as the temperature evolution of the domain structure are investigated. It is shown that in spite of the fact that the room temperature phase III has a triclinic s...

The crystal structure of zirconium oxide nanoparticles was refined by the Rietveld analysis of synchrotron X-ray powder diffraction data measured at 298 K. In the nanoparticles, two phases of tetragonal ZrO(2 - delta) (average particle size: 11 +/- 2 nm) and monoclinic ZrO2 (average particle size: 24 +/- 4 nm) existed, where the weight fractions were estimated to be 84.9 and 15.1 wt%, respectiv...

The PZT material near the morphotropic phase boundary where a monoclinic phase was observed is studied in this paper. A theory of the tetragonal to monoclinic phase transition was developed within the Landau free energy approach. The order parameter is the electric polarization vector. The phase transition from the tetragonal to the monoclinic phase is of the first order near the second order. ...

BACKGROUND Lipases constitute a family of enzymes that hydrolyze triglycerides. They occur in many organisms and display a wide variety of substrate specificities. In recent years, much progress has been made towards explaining the mechanism of these enzymes and their ability to hydrolyze their substrates at an oil-water interface. RESULTS We have determined the DNA and amino acid sequences f...

The Schiff base compounds N,N'-bis[(E)-quinoxalin-2-ylmethylidene]propane-1,3-diamine, C(21)H(18)N(6), (I), and N,N'-bis[(E)-quinoxalin-2-ylmethylidene]butane-1,4-diamine, C(22)H(20)N(6), (II), crystallize in the monoclinic crystal system. These molecules have crystallographically imposed symmetry. Compound (I) is located on a crystallographic twofold axis and (II) is located on an inversion ce...