Search results for "Crystal Structure"
showing 10 items of 15036 documents
CCDC 846271: Experimental Crystal Structure Determination
2012
Related Article: G.Callebaut, S.Mangelinckx, L.Kiss, R.Sillanpaa, F.Fulop, N.De Kimpe|2012|Org.Biomol.Chem.|10|2326|doi:10.1039/c2ob06637h
Synthesis and Structure-Affinity Relationships of Spirocyclic Benzopyrans with Exocyclic Amino Moiety
2019
σ1 and/or σ2 receptors play a crucial role in pathological conditions such as pain, neurodegenerative disorders, and cancer. A set of spirocyclic cyclohexanes with diverse O-heterocycles and amino moieties (general structure III) was prepared and pharmacologically evaluated. In structure-activity relationships studies, the σ1 receptor affinity and σ1:σ2 selectivity were correlated with the stereochemistry, the kind and substitution pattern of the O-heterocycle, and the substituents at the exocyclic amino moiety. cis-configured 2-benzopyran cis-11b bearing a methoxy group and a tertiary cyclohexylmethylamino moiety showed the highest σ1 affinity ( Ki = 1.9 nM) of this series of compounds. In…
CCDC 604222: Experimental Crystal Structure Determination
2007
Related Article: K.Ejsmont, R.Gajda, M.Makowski|2007|Acta Crystallogr.,Sect.C:Cryst.Struct.Commun.|63|o80|doi:10.1107/S0108270106052590
CCDC 1444032: Experimental Crystal Structure Determination
2016
Related Article: Fares Ibrahim Amr, Carlos Vila, Gonzalo Blay, M. Carmen Muñoz and José R. Pedro|2016|Adv.Synth.Catal.|358|1583|doi:10.1002/adsc.201600036
CCDC 2092891: Experimental Crystal Structure Determination
2021
Related Article: Laura Carceller-Ferrer, Carlos Vila, Gonzalo Blay, M. Carmen Muñoz, José R. Pedro|2021|Org.Lett.|23|7391|doi:10.1021/acs.orglett.1c02571
CCDC 1522803: Experimental Crystal Structure Determination
2017
Related Article: Aino J. Karhu, Juho Jämsä, J. Mikko Rautiainen, Raija Oilunkaniemi, Tristram Chivers and Risto S. Laitinen|2017|Z.Anorg.Allg.Chem.|643|495|doi:10.1002/zaac.201700031
Efficient Time Integration of Maxwell's Equations with Generalized Finite Differences
2015
We consider the computationally efficient time integration of Maxwell’s equations using discrete exterior calculus (DEC) as the computational framework. With the theory of DEC, we associate the degrees of freedom of the electric and magnetic fields with primal and dual mesh structures, respectively. We concentrate on mesh constructions that imitate the geometry of the close packing in crystal lattices that is typical of elemental metals and intermetallic compounds. This class of computational grids has not been used previously in electromagnetics. For the simulation of wave propagation driven by time-harmonic source terms, we provide an optimized Hodge operator and a novel time discretizati…
Structural Evolution of Atomically Precise Thiolated Bimetallic [Au12+nCu32(SR)30+n]4– (n = 0, 2, 4, 6) Nanoclusters
2014
A series of all-thiol stabilized bimetallic Au-Cu nanoclusters, [Au(12+n)Cu32(SR)(30+n)](4-) (n = 0, 2, 4, 6 and SR = SPhCF3), are successfully synthesized and characterized by X-ray single-crystal analysis and density functional theory (DFT) calculations. Each cluster consists of a Keplerate two-shell Au12@Cu20 core protected by (6 - n) units of Cu2(SR)5 and n units of Cu2Au(SR)6 (n = 0, 2, 4, 6) motifs on its surface. The size and structural evolution of the clusters is atomically controlled by the Au precursors and countercations used in the syntheses. The clusters exhibit similar optical absorption properties that are not dependent on the number of surface Cu2Au(SR)6 units. Although DFT…
A Unified AMBER-Compatible Molecular Mechanics Force Field for Thiolate-Protected Gold Nanoclusters.
2016
We present transferable AMBER-compatible force field parameters for thiolate-protected gold nanoclusters. Five different sized clusters containing both organo-soluble and water-soluble thiolate ligands served as test systems in MD simulations, and parameters were validated against DFT and experimental results. The cluster geometries remain intact during the MD simulations in various solvents, and structural fluctuations and energetics showed agreement with DFT calculations. Experimental diffusion coefficients and crystal structures were also reproduced with sufficient accuracy. The presented parameter set contains the minimum number of cluster-specific parameters enabling the use of these p…
Electronic Structure and Optical Properties of the Intrinsically Chiral 16-Electron Superatom Complex [Au20(PP3)4]4+
2014
The recently solved crystal structure of the [Au20(PP3)4]Cl4 cluster (PP3: tris(2-(diphenylphophino)ethyl)phosphine) is examined using density functional theory (DFT). The Au20 core of the cluster is intrinsically chiral by the arrangement of the Au atoms. This is in contrast to the chirality of thiolate-protected gold clusters, in which the protecting Au-thiolate units are arranged in chiral patterns on achiral cores. We interpret the electronic structure of the [Au20(PP3)4]Cl4 cluster in terms of the superatom complex model. The 16-electron cluster cannot be interpreted as a dimer of 8-electron clusters (which are magic). Instead, a superatomic electron configuration of 1S(2) 1P(6) 1D(6) …