in the current study, synthesis and characterization of a new nano-structured zirconium(iv)-minoxidil complex (1), where minoxidil, (c9h15n5o; 6-(1-piperidinyl)-2,4-pyrimidinediamine 3-oxide), have been investigated in two different solvents. the compound 1 has been synthesized by sonochemical method in the presence of methanol and monoethylene glycol (meg) as solvents and characterized by scan...

The atomic-scale structure of nanocrystalline ZrO2 obtained by ball milling has been studied using highenergy x-ray diffraction and the atomic pair distribution function technique. The studies show that, upon relatively short milling times, the parent crystalline material, monoclinic ZrO2, evolves into a nanocrystalline phase that is locally similar to monoclinic zirconia but shows a cubic-type...

The title compound, [Fe(C(5)H(5))(C(15)H(14)NO(2))], is a monoclinic polymorph of the previously reported triclinic form [Shi et al. (2006 ▶). Acta Cryst. C62, m407-m410]. The polymorphs feature the same strong intra-molecular N-H⋯O=C hydrogen bonds, but show different packing modes. The mol-ecules in the monoclinic form associate into double chains via O-H⋯O=C and (Cp)C-H⋯O-H inter-actions.

We report a novel phase of carbon possessing a monoclinic C2/m structure (8 atoms/cell) identified using an ab initio evolutionary structural search. This polymorph, which we call M-carbon, is related to the (2x1) reconstruction of the (111) surface of diamond and can also be viewed as a distorted (through sliding and buckling of the sheets) form of graphite. It is stable over cold-compressed g...

A second monoclinic polymorph of 2,4-dimethyl-anilinium chloride, C(8)H(12)N(+)·Cl(-), (I), is reported. The unit-cell dimensions differ from those of the first reported monoclinic form, (II) [Yao (2010 ▶). Acta Cryst. E66, o1563]. Nevertheless, both compounds crystallize in the monoclinic space group P2(1)/n. As in (II), the protonated amine group in (I) acts as a hydrogen-bond donor to the ch...

The asymmetric unit of the title compound, C(10)H(6)N(4)O(4)S(2), contains two independent but similar mol-ecules. The structure is a triclinic polymorph of the monoclinic structure reported previously [Brito, Mundaca, Cárdenas, López-Rodríguez & Vargas (2007 ▶). Acta Cryst. E63, o3351-o3352]. The most obvious difference between the two polymorphs is the C-S-S-C torsion angle [-80.13 (16), -79....

High-temperature phases of hafnium dioxide have exceptionally high dielectric constants and large bandgaps, but quenching them to room temperature remains a challenge. Scaling the bulk form to nanocrystals, while successful in stabilizing the tetragonal phase of isomorphous ZrO2, has produced nanorods with a twinned version of the room temperature monoclinic phase in HfO2. Here we use in situ h...

This study evaluated microstructural and crystallographic phase changes after grinding (G) and regeneration firing/anneling (R) of Y-TZP ceramics. Thirty five bars (LavaTM and Ice Zirkon) were divided: Y-TZP pre-sintered, control (C), regeneration firing (R), dry grinding (DG), dry grinding+regeneration firing (DGR), wet grinding (WG) and wet grinding+regeneration firing (WGR). Grinding was con...