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States Corresponding (states + corresponding)

Distribution by Scientific Domains

Physics and Astronomy	40%
Chemistry	40%

Selected Abstracts

Bound state spectra of the 3D rational potential

INTERNATIONAL JOURNAL OF QUANTUM CHEMISTRY, Issue 5 2008
Amlan K. Roy
Abstract We present bound state spectra of the 3D rational potential, V(r) = r2 + ,r2/(1 + gr2), g > 0, by means of the generalized pseudospectral method. All the 30 states corresponding to n = 0,9 are considered for the first time for a broad range of coupling parameters. These results surpass the accuracy of all other existing calculations published so far except the finite-difference method, which yields similar accuracy as ours. Variation of energies and radial distribution functions is followed with respect to the interaction parameters. Special emphasis has been laid on higher excitations and negative values of the interaction, where relatively less work has been reported. The energy sequence is found to be different for positive and negative interaction; numerically following a mirror-image relationship usually, if not always. Additionally, 20 energy splittings arising from certain levels belonging to n = 0,9 are systematically studied as functions of the potential parameters. Several new states (including the higher ones) are presented. © 2007 Wiley Periodicals, Inc. Int J Quantum Chem, 2008 [source]

Photochemistry of CH3Mn(CO)5: A multiconfigurational ab initio study

JOURNAL OF COMPUTATIONAL CHEMISTRY, Issue 15 2006
Leticia González
Abstract The electronic spectroscopy of CH3Mn(CO)5 has been investigated by means of ab initio multiconfigurational MS-CASPT2/CASSCF calculations. The absorption spectrum is characterized by a series of Metal-Centered (MC) excited states in the UV energy domain (below 290 nm) that could be responsible for the observed photoreactivity starting at 308 nm. The upper part of the spectrum is overcrowded between 264 and 206 nm and dominated by a high density of Metal-to-Ligand-Charge-Transfer (MLCT) states corresponding mainly to 3dMn , ,*CO excitations. A non-negligible contribution of Metal-to-,-Bond-Charge-Transfer (MSBCT) states corresponding to 3dMn , ,*Mn-CH3 excitations is also present in the theoretical spectrum of CH3Mn(CO)5. However, in contrast to other transition metal hydrides and methyl substituted (HMn(CO)5, HCo(CO)4, and CH3Co(CO)4) these MSBCT transitions do not participate to the lowest bands of the spectrum as main contributions. The photochemistry of CH3Mn(CO)5, namely the loss of a CO ligand vs. the metal-methyl bond homolysis, is investigated by means of MS-CASPT2 states correlation diagrams. This study illustrates the complexity of the photodissociation mechanism of this class of molecules, which involves a large number of nearly degenerate electronic states with several channels for fragmentation. © 2006 Wiley Periodicals, Inc. J Comput Chem, 2006 [source]

Simple spin textures in a quantum dot

PHYSICA STATUS SOLIDI (B) BASIC SOLID STATE PHYSICS, Issue 2 2003
M. Ciorga
Abstract Measurements and calculations previously reported for a lateral quantum dot at magnetic fields close to the transition to the maximum density droplet provided evidence that the increase of spin polarisation of a dot with magnetic field is interrupted by spin depolarization events. The loss of spin polarisation is associated with correlated states corresponding to condensation of spin excitons into spin textures. In this paper a detailed experimental and theoretical analysis is performed of the excitation spectra at the first two spin flip events in a few electron quantum dot. In this less complicated regime we are able to identify these correlated states as spin and charge excitons and bi-excitons. In particular we focus on a dot containing eight electrons. Coulomb blockade experiments, supported by detailed calculations, confirm the presence of these correlated states at the second spin flip. [source]

Optical phonons in hexagonal GaN/AlN and GaN/AlGaN superlattices

PHYSICA STATUS SOLIDI (C) - CURRENT TOPICS IN SOLID STATE PHYSICS, Issue 7 2005
V. Yu.
Abstract In this work, by using numerical simulation of the lattice dynamics of hexagonal GaN/AlN superlattices, the microscopic nature of the vibrational states corresponding to the most intense lines in Raman spectra has been established and the interpretation of experimental spectra has been suggested. (© 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source]

Relationships between multiple births and autism spectrum disorders, cerebral palsy, and intellectual disabilities: autism and developmental disabilities monitoring (ADDM) network,2002 surveillance year,

AUTISM RESEARCH, Issue 5 2008
Kim Van Naarden Braun
Abstract Since the 1970s, the prevalence of multiple births (MBs) in the United States has increased significantly. This has been attributed, in large part, to iatrogenic MBs resulting from infertility treatments that include ovulation stimulation. A past study has indicated that children from MBs have an increased prevalence of cerebral palsy (CP). Other studies also have suggested an association between MBs and intellectual disabilities (ID) and autism spectrum disorders (ASDs); however, results have been inconsistent. From the Autism and Developmental Disabilities Monitoring (ADDM) Network, a surveillance project among several US populations, we obtained MB estimates among children born in 1994 and classified by 8 years of age as having: an ASD (n=1,626 total children from 11 sites; 50 born as part of an MB); CP (n=302 total children from 3 sites; 25 born as part of an MB); or ID (n=1,195 total children from 3 sites; 45 born as part of an MB). All three MB estimates were notably higher than age-adjusted expected estimates of naturally conceived MBs derived from 1971 US natality data. However, when MB estimates from the ADDM Network were compared with expected MB estimates derived from 1994 natality data for the states corresponding to the relevant ADDM Network sites, we observed no association with ASDs (observed/expected=1.08 [0.78,1.38]), a moderate, but not statistically significant association with ID (observed/expected=1.34 [0.95,1.73]), and a strong association with CP (observed/expected=2.96 [1.80,4.12]). Further investigation of specific types of MBs (natural vs. iatrogenic) is warranted. [source]