The title compound, [SnCl₂(C₅H₄NS)₂], is the product of reaction of 2,2'-dipyridyl disulfide with tin tetra-chloride. The Sn(IV) atom adopts a distorted octa-hedral geometry, with the two bidentate pyridine-2-thiol-ate ligands forming two planar four-membered chelate rings. The two Sn-Cl, two Sn-N and two Sn-S bonds are in cis, cis and trans configurations, respectively. The crystal grown from ...

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 title compound, [Cu₂Cl₄(C₁₄H₁₄N₂)₂], is a new polymorph of a previously reported compound [Dehghanpour et al. (2011 ▶). Acta Cryst. E67, m1296]. The current polymorph was obtained from an acetonitrile solution of the title compound. Like the first polymorph, it is monoclinic (space group P2₁/c). The unique Cu(II) ion in the title centrosymmetric dinuclear complex is in a distorted trigonal-...

piroxicam has two different crystalline forms (known as needle and cubic forms), that they are different in physicochemical properties such as biological solubility. in the current research, using taguchi experimental design approach the influences of five operating variables on formation of the piroxicam polymorph shapes in recrystallization were studied. the variables include type of solvent,...

The title compound, C10H5FN2, is a monoclinic (P21/c) polymorph of the previously reported triclinic (P-1) form [Anti-pin et al. (2003 ▶). J. Mol. Struct. 650, 1-20]. The 13 non-H atoms in the title polymorph are almost coplanar (r.m.s. deviation = 0.020 Å); a small twist between the fluoro-benzene and dinitrile groups [C-C-C-C torsion angle = 175.49 (16)°] is evident in the triclinic polymorph...

Understanding the polymorphic behavior of active pharmaceutical ingredients is important for formulation purposes and regulatory reasons. Metacetamol is an isomer of paracetamol and it similarly exhibits polymorphism. In the present article, it has been found that one of the polymorphs of metacetamol is only stable under increased pressure, which has led to the conclusion that metacetamol like ...

We present results of computer simulations of homogeneous crystal nucleation in the Gaussian core model. In our simulations, we study the competition between the body-centered-cubic (bcc), face-centered-cubic (fcc), and hexagonal-close-packed crystal phases. We find that the crystal nuclei that form from the metastable fluid phase are typically "mixed"; they do not consist of a single crystal p...

Over the last eight years new theories regarding nucleation, crystal growth, and polymorphism have emerged. Many of these theories were developed in response to observations in nature, where classical nucleation theory failed to account for amorphous mineral precursors, phases, and particle assembly processes that are responsible for the formation of invertebrate mineralized skeletal elements, ...

The metastable ilmenite polymorph of NaNbO(3), instead of the expected perovskite polymorph, may be prepared directly in one step under mild hydrothermal conditions by lowering pH and using close to stoichiometric amounts of metal precursors; in situ energy-dispersive X-ray diffraction shows that crystallisation occurs rapidly via a sequence of intermediate crystalline phases.

Template-free polymorph discrimination of CaCO(3) can be easily realized by a so-called double-jet method in aqueous solution under mild conditions, which may shed new light on the controlled crystallization of other inorganic material systems in which polymorph selection is of critical importance or is highly relevant to their properties.