Results 151 to 160 of about 220,627 (193)

Ring currents in condensed ring systems

International Journal of Quantum Chemistry, 1998
We have studied magnetism and aromaticity of polycyclic ring systems by analyzing ring currents for different circulations in these molecules. The technique employed for calculating ring currents uses correction vectors which implicitly includes all the eigenstates of the Hamiltonian in the space of the chosen configurations.
Anusooya, Y, Chakrabarti, Aparna, Pati, Swapan K, Ramasesha, S   +3 more
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Double Aromaticity and Ring Currents in All‐Carbon Rings

Chemistry – A European Journal, 2009
AbstractDouble aromaticity of neutral, planar rings of carbon atoms is demonstrated through visualisation of the induced ring currents, mapped at the ipsocentric B3LYP/6‐31G(d)//B3LYP/6‐31G(d) level for species C6 to C30, with onset of delocalised current in the in‐plane π system at C10/C11.
Patrick W, Fowler, Noriyuki, Mizoguchi, David E, Bean, Remco W A, Havenith   +3 more
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Aromaticity and Ring Currents

Chemical Reviews, 2001
J A, Gomes, R B, Mallion
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Induced Paramagnetic Ring Currents

Journal of the American Chemical Society, 1966
J. A. Pople, K. G. Untch
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Full Spectral Decomposition of Ring Currents

The Journal of Physical Chemistry A, 2006
Within the ipsocentric method for calculation of molecular magnetic response, projection of perturbed orbitals onto the virtual orbital space allows partition of induced current density into contributions from individual virtual excitations between occupied and unoccupied orbitals, enabling detailed assignment of the origin of currents in, e.g ...
Steiner E., Soncini A., Fowler P. W.
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Ring currents

Progress in Nuclear Magnetic Resonance Spectroscopy, 2000
BCS: Bardeen–Cooper–Schrieffer; BRE: bond resonance energy; CHF: coupled Hartree–Fock; CIS: complexation chemicalshifts; CM: centre of mass; CO: common origin; CPT: charge conjugation-parity inversion-time reversal; CSGT: continuous set of gaugetransformations; CSDGT: continuous set of damped gauge transformations; CTDOCD: continuous transformation of ...
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Ring Current Dynamics

Space Science Reviews, 2006
This chapter reviews the current understanding of ring current dynamics. The terrestrial ring current is an electric current flowing toroidally around the Earth, centered at the equatorial plane and at altitudes of ∼10,000 to 60,000 km. Enhancements in this current are responsible for global decreases in the Earth’s surface magnetic field, which have ...
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“Ring currents” static hypersusceptibilities

International Journal of Quantum Chemistry, 1980
AbstractThe Hückel–London theory has been applied to the calculation of the “ring currents” octopole hypersusceptibilities of a series of conjugated compounds. Our calculations have been performed using fourth‐order Rayleigh–Schrödinger perturbation technique. This is believed to be the first calculation of this kind.
J. Gayoso, B. Maouche, O. Ouamerali, A. Baba‐Ahmed   +3 more
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Topological definition of ring currents

Physical Chemistry Chemical Physics, 2016
A definition of ring currents in a velocity vector field is proposed according to topological criteria: ring currents are axial vortices confined in, or rotating beyond, a separatrix, i.e., the boundary which marks the limits of the vortex.
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