Library

feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 100 (1994), S. 7508-7514 
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: The theory of electron spin-rotational (SR) relaxation in systems with an effective spin Seff=1/2 is formulated in terms of the adiabatic rotation of effective spin (ARES) approach. It is shown that SR relaxation results from the orientational random walk of the axes of the intramolecular electric field potential (ligand field) to which a spin-bearing atomic center is exposed. The validity of the stochastic treatment presented here is not limited by the Redfield conditions. The general expression obtained for the time constant of electron spin relaxation in liquid phase reproduces the well-known result of Hubbard–Atkins–Kivelson theory if it is specialized to the case of systems with weak spin–orbit coupling.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 2
    ISSN: 1573-9171
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract The effect of an external heavy atom on the EPR spectra of radicals in homogeneous liquid solutions was investigated. Broadening of the lines in the EPR spectrum of the fluorescein semiquinone radical in water-ethanol solution was found under the effect of the external heavy atom. It was hypothesized that this broadening is due to an increase in the anisotropy of the g-factor due to potentiation of the spinorbital interaction on contact with the external heavy atom.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 3
    Electronic Resource
    Electronic Resource
    Springer
    Russian physics journal 22 (1979), S. 797-799 
    ISSN: 1573-9228
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 4
    Electronic Resource
    Electronic Resource
    Springer
    Russian physics journal 32 (1989), S. 490-492 
    ISSN: 1573-9228
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract The Liouville equation is considered for the density operator of a triplet center with phenomenological population and decay constants (K+ and K-). In the case of anisotropy of K- with respect to the internal magnetic axis of the triplet, the spin polarization and intensities of the EPR lines of the triplet center in a strong magnetic field are calculated. On this basis, an interpretation of experiments on Si-Si centers in irradiated silicon is given. Quantum-chemical calculations of the model of the center in the form of a cluster OSi4H12 are performed, taking account of the spin-orbital interaction, the anisotropy of which agrees with the EPR spectra of Si-Si centers in silicon.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 5
    Electronic Resource
    Electronic Resource
    Springer
    Russian physics journal 21 (1978), S. 571-574 
    ISSN: 1573-9228
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract A new mechanism is proposed for spin-lattice relaxation (SPL) in the phosphorescent triplet state of a molecule that has no inversion point. The mechanism is based on the fact that the internal spin-orbital interaction in a molecule allows the transition between spin sublevels of the triplet induced by the variable crystal field of the lattice.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 6
    Electronic Resource
    Electronic Resource
    Springer
    Theoretical and experimental chemistry 24 (1988), S. 88-92 
    ISSN: 1573-935X
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract An expression for the initial chemically induced dynamic electron polarization produced according to a triplet mechanism under the conditions of pumping by polarized light has been obtained under the assumption that the fluctuations of the orientation of a molecule in a liquid have the character of an uncorrelated Markov process. The expression obtained is valid for arbitrary values of the magnetic field strength and the viscosity of the solvent. Numerical calculations of the chemically induced dynamic electron polarization have been carried out for slow molecular rotations and in weak magnetic fields.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 7
    Electronic Resource
    Electronic Resource
    Springer
    Theoretical and experimental chemistry 22 (1986), S. 189-192 
    ISSN: 1573-935X
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract It is assumed that orientation fluctuations for molecules in a liquid form an uncorrelated Markov process, and an expression is derived in quadratures for the initial chemical polarization of the electrons formed by the triplet mechanism. The expression applies for any magnetic field strength and solvent viscosity. If the molecular rotations are slow and the magnetic field is weak, one can perform numerical calculations on the electron chemical polarization.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 8
    ISSN: 1573-9171
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Conclusions 1. Restriction of molecular mobility by increasing the viscosity of the medium or including a radical pair (RP) in a micelle is manifested by a significant increase in the polarization amplification factors in comparison to polarization in the same systems in a nonviscous solvent. Restriction of molecular mobility results in an increase in the fraction of RP in which selection can take place with respect to the nuclear spins, and thus in an increase in polarization. 2. Incorporation of a heavy Br atom in the structure of the donor or acceptor results in a decrease in the effects of an external magnetic field and in most cases a decrease in the amplification factors of the PMR lines of the polarized products of the photochemical redox reaction. The cause of this consists of the appearance of a spin-orbital interaction between the radicals in the contact RP. 3. Restriction of molecular mobility for systems with heavy atoms results in a significant decrease in polarization in comparison to polarization in a nonviscous homogeneous solvent. The RP remains in contact for a longer time in a viscous medium or micelle, and the spin-orbital interaction can significantly reduce the spin correlation of the RP, which is also reflected in the low amplification factors.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...