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Polymorphs and Polymorphic Cocrystals of Temozolomide
Chemistry – An Asian Journal, 2008AbstractCrystal polymorphism in the antitumor drug temozolomide (TMZ), cocrystals of TMZ with 4,4′‐bipyridine‐N,N′‐dioxide (BPNO), and solid‐state stability were studied. Apart from a known X‐ray crystal structure of TMZ (form 1), two new crystalline modifications, forms 2 and 3, were obtained during attempted cocrystallization with carbamazepine and 3‐
N Jagadeesh, Babu +3 more
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On the Polymorphism of Aspirin
Angewandte Chemie International Edition, 2007More headaches with aspirin: No new polymorph? Reduction and re-indexing of X-ray data collected on a crystal of the well-known form I of aspirin in a unit cell recently reported for the new form II results in a data set from which this so-called new form can be obtained and even refined isotropically! Form II, if it exists, needs to be identified with
Bond, Andrew +2 more
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Chemical Reviews, 2013
An unambiguous definition of conformational change and conformational polymorphism, as well as a quantitative basis for the likelihood of its appearance, is reviewed. Conformational adjustment and conformational change are different phenomena. Two polymorphs are conformational polymorphs only if their conformations are related by conformational change.
Cruz-Cabeza, A.J., Bernstein, J.
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An unambiguous definition of conformational change and conformational polymorphism, as well as a quantitative basis for the likelihood of its appearance, is reviewed. Conformational adjustment and conformational change are different phenomena. Two polymorphs are conformational polymorphs only if their conformations are related by conformational change.
Cruz-Cabeza, A.J., Bernstein, J.
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Proceedings of the 13th International Conference on Database Theory, 2010
We examine schema mappings from a type-theoretic perspective and aim to facilitate and formalize the reuse of mappings. Starting with the mapping language of Clio, we present a type-checking algorithm such that typable mappings are necessarily satisfiable.
Ryan Wisnesky +2 more
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We examine schema mappings from a type-theoretic perspective and aim to facilitate and formalize the reuse of mappings. Starting with the mapping language of Clio, we present a type-checking algorithm such that typable mappings are necessarily satisfiable.
Ryan Wisnesky +2 more
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The Journal of Physical Chemistry Letters, 2022
Hydrogenated borophenes─borophanes─have recently been synthesized as a new platform for studying low-dimensional borides, but most of their lattice structures remain unknown. Here, we determine the structures of borophane polymorphs on Ag(111) by performing extensive structural search using the cluster expansion method augmented with first-principles ...
Ying Xu +6 more
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Hydrogenated borophenes─borophanes─have recently been synthesized as a new platform for studying low-dimensional borides, but most of their lattice structures remain unknown. Here, we determine the structures of borophane polymorphs on Ag(111) by performing extensive structural search using the cluster expansion method augmented with first-principles ...
Ying Xu +6 more
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Acta Crystallographica Section C Crystal Structure Communications, 2001
Pentacene, C(22)H(14), crystallizes in different morphologies characterized by their d(001)-spacings of 14.1, 14.5, 15.0 and 15.4 A. We have studied the crystal structure of the 14.1 and 14.5 A d-spacing morphologies grown by vapour transport and from solution. We find a close correspondence between the 14.1 A structure reported by Holmes, Kumaraswamy,
Mattheus, C. C. +5 more
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Pentacene, C(22)H(14), crystallizes in different morphologies characterized by their d(001)-spacings of 14.1, 14.5, 15.0 and 15.4 A. We have studied the crystal structure of the 14.1 and 14.5 A d-spacing morphologies grown by vapour transport and from solution. We find a close correspondence between the 14.1 A structure reported by Holmes, Kumaraswamy,
Mattheus, C. C. +5 more
openaire +2 more sources