Results 151 to 160 of about 10,183 (185)
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An investigation into the use of R12, R12 mixtures in air conditioners
International Journal of Refrigeration, 1980Abstract An appraisal of the use of mixed refrigerants is presented following an investigation on the performance of a window air conditioner. This system was chosen because the temperature changes are comparatively large. The important results of the study and proposals to reduce power consumption and achieve optimum performance are described.
P.L. Dhar, A.M.Bin Gadhi
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Avoiding numerical instabilities in R12 calculations through universal R12 consistent basis sets
Chemical Physics Letters, 2003Abstract We show that the incidental numerical instabilities in explicitly correlated coupled cluster R12 (CC-R12) calculations can be a priori removed by using systematically developed R12 suited basis sets. Those are quite different from basis sets developed for conventional calculations mainly in polarization functions.
Pierre Valiron +2 more
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The Journal of Chemical Physics, 2006
Coupled-cluster response theory for vertical excitation energies within the second-order approximate coupled-cluster singles-and-doubles model CC2, including linear-r12 corrections, is derived and implemented for Ansätze 1 and 2 of R12 theory. An orthonormal auxiliary basis set is used for the resolution-of-the-identity approximation in order to ...
Heike, Fliegl +2 more
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Coupled-cluster response theory for vertical excitation energies within the second-order approximate coupled-cluster singles-and-doubles model CC2, including linear-r12 corrections, is derived and implemented for Ansätze 1 and 2 of R12 theory. An orthonormal auxiliary basis set is used for the resolution-of-the-identity approximation in order to ...
Heike, Fliegl +2 more
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Some investigations of the MP2-R12 method
Theoretica Chimica Acta, 1991The MP2-R12 method was introduced by Kutzelnigg and Klopper to overcome the problem caused by truncation of the one electron basis set in correlation energy calculations at the Moller-Plesset second order level of approximation. Here, we have evaluated the integrals required by their simplest scheme using the Rys-quadrature procedure.
Michael J. Bearpark +3 more
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2023
The Minor Planet Electronic Circulars contain information on unusual minor planets, routine data on comets and natural satellites, and occasional editorial announcements. They are published on behalf of Division F of the International Astronomical Union by the Minor Planet Center, Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
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The Minor Planet Electronic Circulars contain information on unusual minor planets, routine data on comets and natural satellites, and occasional editorial announcements. They are published on behalf of Division F of the International Astronomical Union by the Minor Planet Center, Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
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Viscosity of refrigerants R12, R113, and R114 and mixtures of R12 + R114 at high pressure
International Journal of Thermophysics, 1989New viscosity measurements for the gaseous and supercritical state of the halogenated hydrocarbons R12, R113, and R114 and binary mixtures of R12 + R114 of different compositions are presented. The measurements were carried out at superheated and supercritical temperatures from 30 to 200° C and in the pressure range from 1 to 80 bar.
H. Nabizadeh, F. Mayinger
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Linear R12 Terms in Coupled Cluster Theory
2003Highly accurate molecular electronic energies and properties can be obtained computationally when the molecular electronic trial wave function depends explicitly on the inter-electronic distances r ij = |r i − r j | in the system. This has been known since the early days of quantum mechanics [1, 2], but it has proven very difficult to develop generally
Klopper, Wim, Noga, Jozef
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Coupled-cluster theory with simplified linear-r12 corrections: The CCSD(R12) model
The Journal of Chemical Physics, 2005A simplified singles-and-doubles linear-r12 corrected coupled-cluster model, denoted CCSD(R12), is proposed and compared with the complete singles-and-doubles linear-r12 coupled-cluster method CCSD-R12. An orthonormal auxiliary basis set is used for the resolution-of-the-identity approximation to calculate three-electron integrals needed in the linear ...
Heike, Fliegl +2 more
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Metal Science and Heat Treatment, 1966
1. The cutting qualities of tools made of R12 steel are as good as those of cutters made of the more expensive R18 steel. 2. Extensive industrial tests of R12 steel are needed in view of its utilization in industry.
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1. The cutting qualities of tools made of R12 steel are as good as those of cutters made of the more expensive R18 steel. 2. Extensive industrial tests of R12 steel are needed in view of its utilization in industry.
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Multireference R12 Coupled Cluster Theory
2010In order to account for static electron correlation, the explicitly correlated coupled cluster (CC) theory based on the R12 Ansatz is formulated with respect to a multi-determinantal reference using the Brillouin – Wigner (BW) approach. Though the latter avoids appearance of the intruder states, one pays for this desired feature by the loss of size ...
Stanislav Kedžuch +3 more
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