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Katrin Paschke Christian Fiebig Gunnar Blume Alexander Sahm Daniel Jedrzejczyk David Feise Götz Erbert 《Optical Review》2014,21(1):75-78
We demonstrate diode laser modules with high spectral radiance larger than 1 GW/cm2/sr/nm in the visible spectral range. These highly brilliant laser light sources enable the development of next-generation 3D displays. About 1W output power from small-sized modules was achieved at 635 nm by direct diode laser emission and at 530 nm using single pass second harmonic generation (SHG) of a highly brilliant near-infrared laser diode. 相似文献
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Gunnar Karlström 《Theoretical chemistry accounts》1977,44(2):165-169
A new method to perform variational CI calculations on systems containing non-interacting molecules is presented. 相似文献
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A series of o-alkylphenyl alkyl ketones 1 were synthesized by different methods. The presence of a leaving group X adjacent to the carbonyl group is the special peculiarity of these ketones. Upon irradiation the keto carbonyl group of these compounds undergoes an n-pi* excitation followed by a 1,5-hydrogen migration from the o-alkyl substituent to the carbonyl oxygen atom. The thus formed 1,4-diradicals are subject to a very rapid elimination of acid HX, giving 1,5-diradicals. We called this process spin center shift. After intersystem crossing these diradicals cyclize to 1-indanones 20 in good yields. Depending on the solvent and on substituents, o-alkoxyalkyl ketones 22 or benzo[c]furanes 21 are obtained as byproducts. The mechanism of the cyclization was elucidated by quantum chemical calculations and kinetic measurements. 相似文献
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Jose Manuel?Hermida-RamónEmail author Gunnar?Karlstr?m Bengt?Nelander 《Theoretical chemistry accounts》2003,110(3):190-195
The relation between the so called basis set superposition error and intramolecular vibrational frequencies calculated at the Hartree Fock SCF level of approximation was investigated. A linear conformation of HF dimer was chosen as test system for the investigation. It was found that the direct basis set superposition error for the studied system is rather small. It was further found that the shifts are mainly determined by the geometry parameters of the system.
AcknowledgementsJ. M. H.-R. wishes to thank the Ministerio de Educación, Cultura y Deporte for the award of a research grant. 相似文献