Search results for "Carbyne"

showing 3 items of 3 documents

Calculation of size‐intensive transition moments from the coupled cluster singles and doubles linear response function

1994

Coupled cluster singles and doubles linear response (CCLR) calculations have been carried out for excitation energies and dipole transition strengths for the lowest excitations in LiH, CH+, and C4and the results compared with the results from a CI-like approach to equation of motion coupled cluster (EOMCC). The transition strengths are similar in the two approaches for single molecule calculations on small systems. However, the CCLR approach gives size-intensive dipole transition strengths, while title EOMCC formalism does not. Thus, EOMCC calculations can give unphysically dipole transition strengths, e.g., in EOMCC calculations on a sequence of noninteracting LiH systems we obtained a neg…

DipolesGeneral Physics and AstronomySmall systemsExcitation ; Dipoles ; Lithium Hydrides ; Carbynes ; Cations ; Molecular Ions ; Carbon Molecules ; Equations Of Motion ; Correlations ; Response FunctionsPhysics and Astronomy (all)CationsMoleculePhysical and Theoretical Chemistry:FÍSICA::Química física [UNESCO]ExcitationCorrelationsChemistryEquations of motionCarbon MoleculesLinear response functionUNESCO::FÍSICA::Química físicaFormalism (philosophy of mathematics)DipoleCoupled clusterLithium HydridesCarbynesResponse FunctionsAtomic physicsEquations Of MotionMolecular IonsExcitationThe Journal of Chemical Physics
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Chiral diphosphine derivatives of alkylidyne tricobalt carbonyl clusters – A comparative study of different cobalt carbonyl (pre)catalysts for (asymm…

2016

Reaction of the tricobalt carbyne cluster [Co-3(mu(3)-CH)(CO)(9)] with chiral diphosphines of the Josiphos and Walphos families affords the new clusters [Co-3(mu(3)-CH)(CO)(7)(P-P*)] in good yield (P-P* = J004 (1), J005 (2), J007 (3), W001 (4), W003 (5)). The new alkylidyne tricobalt clusters, and the previously known [Co-3(mu(3)-CH)(CO)(7)(mu-J003)], have been tested as catalysts/catalyst precursors for intermolecular Pauson-Khand cyclization, using norbornene and phenylacetylene as substrate. The diphosphine-substituted tricobalt carbonyl clusters proved to be viable catalysts/catalyst precursors that gave products in moderate to good yields, but the enantiomeric excesses were low. When t…

Pauson-Khand reactioncatalysis010405 organic chemistryStereochemistryPauson–Khand reactionCarbynechirality010402 general chemistry01 natural sciencesMedicinal chemistry0104 chemical sciencesCatalysisInorganic Chemistrychemistry.chemical_compoundchemistryPhenylacetyleneDiphosphinesenantioselectivityMaterials ChemistryPhysical and Theoretical ChemistryChirality (chemistry)clusterta116PhosphineNorbornenePolyhedron
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CCDC 116236: Experimental Crystal Structure Determination

1999

Related Article: H.Braunschweig, M.Koster, K.W.Klinkhammer|1999|Angew.Chem.,Int.Ed.|38|2229|doi:10.1002/(SICI)1521-3773(19990802)38:15<2229::AID-ANIE2229>3.0.CO;2-#

Space GroupCrystallographyCrystal SystemCrystal StructurePentacarbonyl-bis(eta^5^-cyclopentadienyl)-(mu~2~-BB'-bis(dimethylimino)diboryloxycarbyne-BC)-di-molybdenumCell ParametersExperimental 3D Coordinates
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