The structures of nanocrystals consisting of 70% vinylidene fl uoride and 30% trifl uoroethylene made by Langmuir–Blodgett deposition were studied using transmission electron microscopy and electron diffraction. Highly ordered nanocrystals with sizes ranging from 100 nm to 4 μm were grown on Langmuir–Blodgett fi lms at a deposition surface pressure of 20 mN m−1. Electron diffraction patterns fr...

A second monoclinic polymorph of methyl 4-hydroxy-benzoate, C(8)H(8)O(3), is reported. The unit-cell dimensions are different from those of the previously reported monoclinic form [Vujovic & Nassimbeni (2006 ▶). Cryst. Growth Des.6, 1595-1597]. The asymmetric unit contains three crystallographically independent mol-ecules, as observed in the previous form. The crystal structure is stabilized by...

The dynamics of singlet fission (SF) are studied in monoclinic and orthorhombic crystals of 1,6-diphenyl-1,3,5-hexatriene. Picosecond time-resolved fluorescence measurements and the presence of a strong magnetic field effect indicate that up to 90% of the initially excited singlets undergo SF in both forms. The initial SF and subsequent triplet pair dissociation rates are found to be more rapid...

We first review earlier work in which we computed the first-principles structural, vibrational, and lattice dielectric properties of the cubic, tetragonal, and monoclinic phases of ZrO2 and HfO2. We then discuss two approaches to the construction of realistic models of amorphous ZrO2: a bmelt-and-quenchQ ab-initio molecular dynamics approach, and an bactivation–relaxation techniqueQ. The struct...

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 ...

Two different crystal forms of human thioredoxin peroxidase-B have been grown by vapour diffusion using polyethylene glycol 400 as a precipitant. Monoclinic P21 crystals were grown from freshly purified protein, whilst orthorhombic P212121 crystals were grown from purified protein that had been stored in ammonium sulfate, but otherwise under the same conditions. The diffraction from both crysta...

Thermal and structural austenite to martensite reversible transition was studied in melt spun ribbons of Ni50Mn40Sn5Co5, Ni50Mn37.5Sn7.5Co5 and Ni50Mn35Sn10Co5 (at. %) alloys. Analysis of X-ray diffraction patterns confirms that all alloys have martensitic structure at room temperature: four layered orthorhombic 4O for Ni50Mn40Sn5Co5, four layered orthorhombic 4O and seven-layered monoclinic 14...

Two polymorphic structures of the Schiff base 2-1-[(2-aminophenyl)imino]ethylphenol, compound (1), C14H14N2O are reported. Depending on the solvent used for recrystallization it crystallizes as either a monoclinic or an orthorhombic polymorph. The monoclinic form, polymorph [1] contains three, while the orthorhombic polymorph [2] contains only one molecule in the asymmetric unit. In both polymo...

The crystal structure of the title compound, [C(NH(2))(3)](6)[Mo(7)O(24)]·H(2)O, previously determined at room temperature in the monoclinic space group C2/c from Weissenberg techniques [Don & Weakley (1981 ▶). Acta Cryst. B37, 451-453], has been redetermined from low-temperature single-crystal data in the monoclinic space group P2(1)/c. The asymmetric unit contains one hepta-molybdate anion, s...

We have studied the surfaces of zirconia (ZrO2) by first-principles calculations using density functional theory. We predict surface energies and relaxations for the principal surfaces of different bulk phases of zirconia. We find that the stoichiometric tetragonal~111! and monoclinic~1̄11! are the most stable surfaces. We find a strong linear correlation between surface energies before and afte...