The quadrupole coupling constants in solids usually depend on temperature (see f.e. Ref. [1 — 8 ]). This can be explained by the change of vibration amplitudes of molecules, but the influence of the volume expansion on the electric field gradient has also to be taken into account [4], For 185Re and 187Re in some peirhenates NQR measurements have been reported [9 — 16]. With the exception of NH ...

We investigated microscopic lattice states in the donor-acceptor ionic Mott insulator, tetrathiafulvalene-bromanil (TTF-BA), by $^{79}\mathrm{Br}\text{\ensuremath{-}}$nuclear quadrupole resonance (NQR) spectroscopy to explore cross-correlated fluctuations between spin, charge, and lattice. A ferroelectric transition with dimerization is captured a NQR line splitting critical exponent $\ensurema...

The quantitation of intracellular sodium ion concentration [Na+]in perfused organs using NMR spectroscopy requires a knowledge of the extent of visibility of the 23Na resonance and of the intracellular volume of the organ. We have used a multinuclear NMR approach, in combination with the extracellular shift reagent dysprosium (III) tripolyphosphate, to determine the NMR visibility of intra- and...

The mechanism by which CIactivates the oxygen-evolving complex (OEC) of Photosystem II (PS II) in spinach was studied by 3SCI-NMR spectroscopy and steady-state measurements of oxygen evolution. Measurements of the excess 35Cl-NMR linewidth in dark-adapted, CI--depleted thylakoid and Photosystem I1 membranes show an overall hyperbolic decrease which is interrupted by sharp increases in linewidth...

We performed 121/123Sb-nuclear quadrupole resonance (NQR) measurements on the superconducting (SC) line-nodal material CaSb2 in order to investigate electronic properties normal and SC states from a microscopic point of view. In state, nuclear spin-lattice relaxation rate 1/T1 for Sb(1) site, which is responsible parts, approximately proportional temperature, indicating conventional Fermi liqui...