A5020108640- Crystallization and Solubility Studies
- X-ray Diffraction in Crystallography
- Crystallography and molecular interactions
- Solid-state spectroscopy and crystallography
- nanoparticles nucleation surface interactions
- Liquid Crystal Research Advancements
- Calcium Carbonate Crystallization and Inhibition
- Enzyme Structure and Function
- Crystal Structures and Properties
- Optical and Acousto-Optic Technologies
- Chemical Thermodynamics and Molecular Structure
- Mineralogy and Gemology Studies
- Glass properties and applications
- Material Dynamics and Properties
- Force Microscopy Techniques and Applications
- Nonlinear Optical Materials Research
- Molecular spectroscopy and chirality
- Chemical and Physical Properties in Aqueous Solutions
- Photochromic and Fluorescence Chemistry
- Geological and Geochemical Analysis
- Spectroscopy and Quantum Chemical Studies
- Analytical Chemistry and Chromatography
- Luminescence and Fluorescent Materials
- Photoreceptor and optogenetics research
- Organic Electronics and Photovoltaics
New York University
2015-2024
Instituto Andaluz de Ciencias de la Tierra
2019
Institute of Medicinal Molecular Design
2017-2018
Courant Institute of Mathematical Sciences
2017
St Petersburg University
2002-2012
Institute of Organic Synthesis and Photoreactivity
2011
Institute of Precambrian Geology and Geochronology
2006
Paul Drude Institute for Solid State Electronics
2003
Crystals of a variety substances including elements, minerals, simple salts, organic molecular crystals, and high polymers forgo long-range translational order by twisting bending as they grow. These deviations have been observed in crystals ranging size from nanometers to centimeters. How why so many materials choose dramatic non-crystallographic distortions is analyzed, with an emphasis on crystal chemistries that give rise stresses operating either surfaces crystallites or within the bulk.
Crystal structures of four new coumarin polymorphs were solved by crystal structure prediction method and their lattice free energies calculated advanced techniques.
Trimorphic paracetamol, one of the most commonly used analgesic and antipyretic drugs, has been a model system for studying transformations among phases molecular crystalline materials. During crystallization from melt glass above 0 °C, three new polymorphs paracetamol (N-acetyl-para-aminophenol or acetaminophen) were discovered, doubling number known ambient forms. The crystal structure form was solved using combination powder X-ray diffraction computational techniques. Growth kinetics...
Crystals grow in the mind's eye by addition of small units to a monolith each part which is fixed translational relation every other part. Here, it shown that growth can induce reversible twisting and untwisting macroscopic crystals hippuric acid (N-benzoylglycine, C(9)H(9)NO(3)) on scale radians. growing undercooled melts twist about axis elongation. At same time undone new elastic stresses build up as crystal thickens. The dynamic interplay ultimately fixes morphology. A correspondence...
Banded spherulites of aspirin have been crystallized from the melt in presence salicylic acid either generated decomposition or added deliberately (2.6-35.9 mol %). Scanning electron microscopy, X-ray diffraction analysis, and optical polarimetry show that are composed helicoidal crystallites twisted along <010> growth directions. Mueller matrix imaging reveals radial oscillations not only linear birefringence, but also circular whose origin is explained through slight (∼1.3°) systematic...
Polymorphism of aspirin (acetylsalicylic acid), one the most widely consumed medications, was equivocal until structure a second polymorph II, similar in to original form I, reported 2005. Here, third ambient is described. It crystallized from melt, and its determined using combination X-ray powder diffraction analysis crystal prediction algorithms.
Structures of the α and β phases resorcinol, a major commodity chemical in pharmaceutical, agrichemical, polymer industries, were first polymorphic pair molecular crystals solved by X-ray analysis. It was recently stated that "no additional can be found under atmospheric conditions" (Druzbicki, K. et al. J. Phys. Chem. B 2015, 119, 1681). Herein is described growth structure new ambient pressure phase, ε, through combination optical crystallography computational crystal prediction...
D-Mannitol belongs to a large and growing family of crystals with helical morphologies (Yu, L. J. Am. Chem. Soc.2003, 125, 6380). Two polymorphs D-mannitol, α δ, when grown in the presence additives such as poly(vinylpyrrolidone) (PVP) or D-sorbitol, form ring-banded spherulites composed handed fibrils, where helix axes correspond radial growth directions. The two helices opposite senses PVP but same sense D-sorbitol. characteristic dimensions including thickness, aspect ratio, pitch, were...
X-ray powder diffraction and crystal structure prediction algorithms are used in synergy to establish the of eighth polymorph ROY, form R05.
The recently discovered glass-crystal (GC) growth mode in some glass-forming liquids is characterized by strong and abrupt rate enhancement just the vicinity of glass transition temperature. GC previously has been observed only 10 compounds. data on testosterone propionate presented here indicate fastest acceleration to date. Moreover, first compound show a helically twisted morphology concomitant with growth. It stated that an aryl ring prerequisite growth, but obviates claim.
Abstract Ferdinand Bernauer proposed in his monograph, “ Gedrillte” Kristalle (1929), that a great number of simple, crystalline substances grow from solution or the melt as polycrystalline spherulites with helically twisting radii give rise to distinct bull′s‐eye patterns concentric optical bands between crossed polarizers. The idea many common molecular crystals can be induced mesoscale helices is remarkable proposition poorly grounded theories pattern formation. Recent reinvestigation one...
Crystal optical properties of banded spherulites 21 different compounds--molecular crystals, polymers, and minerals--with helically twisted fibers were analyzed with Mueller matrix polarimetry. The well-established radial oscillations in linear birefringence many polycrystalline ensembles is accompanied by circular that cannot be explained the natural activity corresponding compounds, some which are centrosymmetric crystalline state. shown to a consequence misoriented, overlapping...
Accounting for the interactions of light with heterogeneous, anisotropic, absorbing, optically active media is part characterization complex, transparent materials. Stained biological structures in thin tissue sections share many these features, but systematic optical analyses beyond employ simple petrographic microscopes have not be established. Here, this accounting made polycrystalline, spherulitic bundles twisted d-mannitol lamellae grown from melts containing light-absorbing molecules....
Dislocations in molecular crystals remain terra incognita. Owing to the complexity of structure, dislocations can be difficult understand using only foundational concepts devised over decades for hard materials. Herein, we review generation, and physicochemical consequences crystals. Unlike metals, ceramics, semiconductors, are often characterized by flexible building units low symmetry, thereby limiting analysis, complicating modeling, prompting new approaches elucidate their role...
Aberrant crystallization within the human body can lead to several disease states or adverse outcomes, yet much remains be understood about critical stages leading these events, which include crystal nucleation and growth, aggregation, adhesion of crystals cells. Kidney stones, are aggregates single with physiological origins, particularly illustrative pathological crystallization, 10% U.S. population experiencing at least one stone occurrence in their lifetimes. The record kidney stones is...
Many molecular crystals (approximately one third) grow as twisted, helicoidal ribbons from the melt, and this preponderance is even higher in restricted classes of materials, for instance, charge-transfer complexes. Previously, twisted crystallites such complexes present an increase carrier mobilities. Here, effect twisting on charge mobility better analyzed a monocomponent organic semiconductor, 2,5-bis(3-dodecyl-2-thienyl)-thiazolo[5,4-d]thiazole (BDT), that forms with varied pitches makes...
Many crystals grow as banded spherulites from the melt with an optical rhythm indicative of helicoidal twisting. In this work, 23 41 charge transfer complexes (CTCs) are grown twisted morphologies. As a group, CTCs more commonly twist (56%) than molecular arbitrarily chosen in our previous research (31%). To analyze effect twisting on transport, three tetracyanoethylene-based phenanthrene (PhT), pyrene (PyT), and perylene characterized. PhT PyT subject to mobility measurements using organic...
Helicoidal crystallites in rhythmically banded spherulites manifest spectacular optical patterns small molecules and polymers. It is shown that concentric bands indicating crystallographic orientations typically lose coherence (in-phase twisting) with growth from the center of nucleation. Here, to increase as twist period decreases for seven molecular crystals grown melt. This dependence was correlated crystallite fiber thickness length, well branching frequency, a parameter extracted...
Significance Molecular mechanisms of crystal growth from solution remain ill-defined. Scanning probe microscopies have begun to illustrate what was before insightful theory. The in situ observations described here for hexagonal l -cystine crystals, which are known form kidney stones, demonstrate that crystals with certain symmetries can exhibit unusual structural and behaviors produce unexpected deceptive morphological features. Such features appear violate a classic theory enshrined more...
A new inclusion compound consisting of a guanidinium 1,3,5-tri(4-sulfophenyl)benzene (G3TSPHB) host framework containing isophorone guests that surround isolated and seemingly inaccessible pockets was amenable to guest exchange with hexafluorobenzene (HFB) through single crystal–single crystal transformation (SCSCT). Single-crystal X-ray diffraction intermediate states, from the parent G3TSPHB·(isophorone)3.7·(methanol)5.4 final state G3TSPHB·(isophorone)3.1·(HFB)2·(methanol)2, indicated...
Two new metastable polymorphs of the tuberculosis drug isoniazid, considered monomorphic for sixty years, were discovered using melt crystallization and nanoscale confinement.