Highly accurate potential-energy and dipole moment surfaces for vibrational state calculations of methane

<p>Diffusion Monte Carlo (DMC) and Reptation Monte Carlo (RMC) methods, have been applied to study some properties of the NaK molecule. Hartree-Fock (HF), Density Functional (DFT) and single and double configuration interaction (SDCI) wavefunctions with a valence quadruple zeta atomic natural orbital (VQZ/ANO) basis set were used as trial wavefunctions. Values for the potential energy curve, dissociation energy and dipole moment were calculated for all methods and compared with experimental results and previous theoretical derivations. Quantum Monte Carlo (QMC) calculations were shown to be useful methods to recover correlation in NaK, essential to obtain a reasonable description of the molecule. The equilibrium distance—interpolated from the potential energy curves—yield a value of 3.5 Å, in agreement with the experimental value. The dissociation energy, however, is not as good. In this case, a conventional CCSD(T) calculation with an extended aug-pc-4 basis set gives a much better agreement to experiment. On the contrary, the CCSD(T), other MO and DFT methods are not able to reproduce correctly the large dipole moment of this molecule. Even DMC methods with a simple HF trial wavefunction are able to give a better agreement to experiment. RMC methods are even better, and the value obtained with a B3LYP trial wavefunction is very close to the experimental one.</p>

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Accurate theoretical near-equilibrium potential energy and dipole moment surfaces of HgClO and HgBrO

The Journal of Chemical Physics ◽

10.1063/1.1652435 ◽

2004 ◽

Vol 120 (14) ◽

pp. 6585-6592 ◽

Cited By ~ 10

Author(s):

Nikolai B. Balabanov ◽

Kirk A. Peterson

Keyword(s):

Dipole Moment ◽

Potential Energy ◽

Equilibrium Potential

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AIM study on the transferability of the oxygen atom in linear ethers

Canadian Journal of Chemistry ◽

10.1139/v00-148 ◽

2000 ◽

Vol 78 (12) ◽

pp. 1535-1543 ◽

Cited By ~ 32

Author(s):

Antonio Vila ◽

Enrique Carballo ◽

Ricardo A Mosquera

Keyword(s):

Dipole Moment ◽

Oxygen Atom ◽

Potential Energy ◽

Critical Points ◽

Wave Functions ◽

Electron Population ◽

Alkyl Radicals ◽

Energy Interaction ◽

Interaction Dipole Moment ◽

Oxygen Atoms

The integrated values of the electron population, electron energy, nucleuselectron potential energy interaction, dipole moment and volume of the oxygen atoms, and the main properties of the OC bond critical points, were determined by employing the theory of atoms in molecules and 6-31++G**//6-31G* wave functions for a series of 25 unbranched alkyl monoethers. These results were used to assess the degree of approximate transferability of the oxygen atom along this series in terms of the particular alkyl radicals bonded to it. It has been found that a set of six different oxygen atoms is necessary to classify all the computed values. It can be established that the oxygen atoms bonded to propyl and larger radicals can be treated, in practice, as a transferable fragment, while those bonded to at least one smaller radical are specific. Though the total HF energy and the available experimental heats of formation are well fitted by a traditional additivity scheme that distinguishes only among O, CH2, and CH3 units, it has been found that the energy properties are influenced by the size of the molecule.Key words: transferability, AIM theory, ethers.

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Quantum and classical IR spectra of (HCOOH)2, (DCOOH)2 and (DCOOD)2 using ab initio potential energy and dipole moment surfaces

Faraday Discussions ◽

10.1039/c8fd00077h ◽

2018 ◽

Vol 212 ◽

pp. 33-49 ◽

Cited By ~ 7

Author(s):

Chen Qu ◽

Joel M. Bowman

Keyword(s):

Dipole Moment ◽

Potential Energy ◽

Ir Spectra ◽

Ab Initio ◽

Ir Spectrum ◽

Quantum Calculation

Full-dimensional (24 modes) quantum calculation of the IR spectrum of (DCOOD)2, and comparison with classical MD one.

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Investigation of rotational state-changing collisions of C2N− ions with helium

Proceedings of the International Astronomical Union ◽

10.1017/s1743921319007580 ◽

2019 ◽

Vol 15 (S350) ◽

pp. 443-444

Author(s):

Jan Franz ◽

Francesco Antonio Gianturco

Keyword(s):

Dipole Moment ◽

Potential Energy ◽

Potential Energy Surface ◽

Cross Sections ◽

Energy Surface ◽

Inelastic Collisions ◽

Atomic Gases ◽

Molecular Anion ◽

Helium Atoms ◽

Molecular Anions

AbstractThe cross sections for rotational inelastic collisions between atoms and a molecular anion can be very large, if the anion has a dipole moment. This makes molecular anions very efficient in cooling atomic gases. We address rotational inelastic collisions of Helium atoms with the molecular anion C2N–. Here we present preliminary calculations of the potential energy surface.

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Elektrisches Dipolmoment von TlBr und TlJ

Zeitschrift für Naturforschung A ◽

10.1515/zna-1971-1105 ◽

1971 ◽

Vol 26 (11) ◽

pp. 1809-1812 ◽

Cited By ~ 1

Author(s):

E. Tiemann

Keyword(s):

Dipole Moment ◽

Electric Dipole Moment ◽

Electric Dipole ◽

Vibrational State ◽

Stark Effect ◽

Dipole Moments ◽

Electric Dipole Moments ◽

Ground Vibrational State ◽

Rotational Transitions

Stark-effect measurements on pure rotational transitions of TlBr and Til are described. The derived electric dipole moments of the most abundant isotopic molecules on the ground vibrational state are:205TL79Br : | μ0| = (4.493 ± 0.050) D , 205Tl127 I | μ 0| =(4.607 ± 0.070) D .The electric dipole moment of 205Tl19F | μ 0|=4.2282 (8) D was used as standard.

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