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91.
In this paper we report the calculation of molecular electric response properties with the help of explicitly time-dependent configuration interaction (TD-CI) methods. These methods have the advantage of being applicable (within the limitations of the time-dependent Schrodinger equation) to time-dependent perturbations of arbitrary shape and strength. Three variants are used to solve the time-dependent electronic Schrodinger equation, namely, the TD-CIS (inclusion of single excitations only), TD-CISD (inclusion of single and double excitations), and TD-CIS(D) (single excitations and perturbative treatment of double excitations) methods and applied for illustration to small molecules, H(2) and H(2)O. In the calculation, slowly varying off-resonant electric fields are applied to the molecules and linear (polarizabilities) and nonlinear (hyperpolarizabilities, harmonic generation) response properties are determined from the time-dependent dipole moments. 相似文献
92.
Bisaminophosphanes – Synthesis, Structure, and Reactivity Different pathways for the synthesis of bis(alkylamino)phosphanes RP(N(H)R′)2 are described. t‐BuP(N(H)‐ Dipp)2 (Dipp = 2,6‐i‐Pr2–C6H3) was structurally characterized by single crystal X‐ray diffraction. The reactivity of the compounds was examplarily investigated using t‐BuP(N(H)t‐Bu)2. Its reaction with Me3Al and R2AlH (R = Me, Et, i‐Bu) in 1 : 1 and 1 : 2 stoichiometrie yield monosubstituted compounds of the type t‐BuP(N(H)t‐Bu)(N(AlR2)t‐Bu). 相似文献
93.
Tillmann Jentsch Andrei Moroianu Uwe Semmelmann 《Differential Geometry and its Applications》2013,31(1):104-111
We describe extrinsic hyperspheres and totally geodesic hypersurfaces in manifolds with special holonomy. In particular we prove the nonexistence of extrinsic hyperspheres in quaternion-Kähler manifolds. We develop a new approach to extrinsic hyperspheres based on the classification of special Killing forms. 相似文献
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Schkolnik G Utesch T Salewski J Tenger K Millo D Kranich A Zebger I Schulz C Zimányi L Rákhely G Mroginski MA Hildebrandt P 《Chemical communications (Cambridge, England)》2012,48(1):70-72
We present a novel approach for determining the strength of the electric field experienced by proteins immobilised on membrane models. It is based on the vibrational Stark effect of a nitrile label introduced at different positions on engineered proteins and monitored by surface enhanced infrared absorption spectroscopy. 相似文献
96.
Rippers Y Utesch T Hildebrandt P Zebger I Mroginski MA 《Physical chemistry chemical physics : PCCP》2011,13(36):16146-16149
Structural models for the Ni-B state of the wild-type and C81S protein variant of the membrane-bound [NiFe] hydrogenase from Ralstonia eutropha H16 were derived by applying the homology model technique combined with molecular simulations and a hybrid quantum mechanical/molecular mechanical approach. The active site structure was assessed by comparing calculated and experimental IR spectra, confirming the view that the active site structure is very similar to those of anaerobic standard hydrogenases. In addition, the data suggest the presence of a water molecule in the second coordination sphere of the active centre. 相似文献
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99.
Tillmann B Rusconi E Traube C Butterworth B Umiltà C Peretz I 《The Journal of the Acoustical Society of America》2011,130(6):4089-4096
Congenital amusia is a lifelong disorder of music processing that has been ascribed to impaired pitch perception and memory. The present study tested a large group of amusics (n=17) and provided evidence that their pitch deficit affects pitch processing in speech to a lesser extent: Fine-grained pitch discrimination was better in spoken syllables than in acoustically matched tones. Unlike amusics, control participants performed fine-grained pitch discrimination better for musical material than for verbal material. These findings suggest that pitch extraction can be influenced by the nature of the material (music vs speech), and that amusics' pitch deficit is not restricted to musical material, but extends to segmented speech events. 相似文献
100.
Using a recent theorem of Galatius, we identify the map on stablehomology induced by Artin's injection of the braid group βninto the automorphism group of the free group Aut Fn. 相似文献