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Related papers: Theory of nuclear spin conversion in ethylene

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A complete theoretical model of the nuclear spin conversion in 13CH3F induced by intramolecular ortho-para state mixing is proposed. The model contains parameters determined from the level-crossing spectra of the 13CH3F spin conversion.…

Chemical Physics · Physics 2007-05-23 Pavel L. Chapovsky

Theoretical model of the nuclear spin conversion in formaldehyde (H2CO) has been developed. The conversion is governed by the intramolecular spin-rotation mixing of molecular ortho and para states. The rate of conversion has been found…

Chemical Physics · Physics 2009-11-06 Pavel L. Chapovsky

Except for ortho- and para-H2, very little is known about nuclear spin isomers (or spin modifications) of molecules. The main reason is the lack of practical enrichment techniques. Recently a few enrichment methods were developed, which…

Chemical Physics · Physics 2007-05-23 P. L. Chapovsky , L. J. F. Hermans

The symmetrized contribution of E-type spin-rotation interaction to conversion between spin modifications of E- and A_1-types in molecules with C_{3v}-symmetry is considered. Using the high-J descending of collisional broadening for…

Chemical Physics · Physics 2009-10-31 K. I. Gus'kov

A theoretical model of hyperfine spectra of nuclear spin conversion of molecular isomers has been developed. The model takes into account the nuclear spin-spin and spin-rotation interactions, as well as the saturation of intramolecular…

Chemical Physics · Physics 2009-11-06 Pavel L. Chapovsky

Electron spin echo envelope modulation (ESEEM) has been observed for the first time from a coupled hetero-spin pair of electron and nucleus in liquid solution. Previously, modulation effects in spin echo experiments have only been described…

A theoretical model of nuclear spin conversion in molecules controlled by an external electromagnetic radiation resonant to rotational transition has been developed. It has been shown that one can produce an enrichment of spin isomers and…

Chemical Physics · Physics 2009-11-06 P. L. Chapovsky

Theoretical model of the coherent control of nuclear spin isomers by microwave radiation has been developed. Model accounts the M-degeneracy of molecular states and molecular center-of-mass motion. The model has been applied to the 13CH3F…

Chemical Physics · Physics 2009-11-07 O. I. Permyakova , E. Ilisca , P. L. Chapovsky

Water exists in two forms, para and ortho, that have nuclear spin states with different symmetries. Here we report the conversion of fullerene-encapsulated para-water to ortho-water. The enrichment of para-water at low temperatures is…

We report a novel phenomenon intimately related to the spin-triplet superconductivity. It is well known that the spin susceptibility decreases below the superconducting transition temperature in almost all superconductors because of…

Superconductivity · Physics 2015-10-28 K. Ishida , M. Manago , T. Yamanaka , H. Fukazawa , Z. Q. Mao , Y. Maeno , K. Miyake

A novel neutron spin resonance technique is presented based on the well-know neutron spin echo method. In a first proof-of-principle measurement using a monochromatic neutron beam, it is demonstrated that relative velocity changes of down…

Instrumentation and Detectors · Physics 2016-04-11 Florian M. Piegsa , Patrick Hautle , Christian Schanzer

One of the important issues of molecular spintronics is the control and manipulation of charge transport and, in particular, its spin polarization through single-molecule junctions. Using $ab$ $initio$ calculations, we explore…

Mesoscale and Nanoscale Physics · Physics 2019-09-04 Dongzhe Li , Yannick J. Dappe , Alexander Smogunov

The nucleus $^{180}$Hf is one of the most primary of examples of an axially symmetric prolate rotor. Combined with the presence of high-$K$ isomers, spectroscopic studies can provide important information on the nature of its…

We report on the using of torsion-rotational transitions in the CH3OH and (13)CH3OH molecules to evaluate possible variations of the physical constant mu=m_e/m_p - the electron-to-proton mass ratio - from spectral observations of emission…

Astrophysics of Galaxies · Physics 2024-05-09 J. S. Vorotyntseva , S. A. Levshakov

The laws of quantum mechanics are often tested against the behaviour of the lightest element in the periodic table, hydrogen. One of the most striking properties of molecular hydrogen is the coupling between molecular rotational properties…

The method of unitary transformations generates five classes of leading-order reducible chiral four-nucleon interactions which involve pion-exchanges and a spin-spin contact-term. Their first-order contributions to the energy per particle…

Nuclear Theory · Physics 2016-02-17 N. Kaiser , R. Milkus

We report on hyperpolarization of quadrupolar (I=3/2) 131Xe via spin-exchange optical pumping. Observations of the 131Xe polarization dynamics show that the effective alkali-metal/131Xe spin-exchange cross-sections are large enough to…

We have observed millisecond-long coherent evolution of nuclear spins in a quantum wire at 1.2 K. Local, all-electrical manipulation of nuclear spins is achieved by dynamic nuclear polarization in the breakdown regime of the Integer Quantum…

Mesoscale and Nanoscale Physics · Physics 2009-10-01 A. Corcoles , C. J. B. Ford , M. Pepper , G. A. C. Jones , H. E. Beere , D. A. Ritchie

The water molecule occurs in two nuclear-spin isomers that differ by the value of the total nuclear spin of the hydrogen atoms, i.e., $I=0$ for para-H$_2$O and $I=1$ for ortho-H$_2$O. Spectroscopic transitions between rovibrational states…

Atomic Physics · Physics 2022-06-08 Andrey Yachmenev , Guang Yang , Emil Zak , Sergei Yurchenko , Jochen Küpper

Spin observables of a binary reaction $1+2\to 3+4$ are discussed at the threshold in general form using P-parity and angular momentum conservation. General formulae for polarization transfer, spin-spin correlation parameters in the initial…

Nuclear Theory · Physics 2007-05-23 Yu. N. Uzikov
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