Recent neutron scattering, nuclear magnetic resonance, and scanning tunneling microscopy experiments have yielded valuable new information on the interplay between charge and spin density wave order and superconductivity in the cuprate superconductors, by using an applied perpendicular magnetic field to tune the ground state properties. We compare the results of these experiments with the predi...

Fully coupled four-dimensional quantum-mechanical calculations are presented for intermolecular vibrational states of rigid carbon dioxide dimer for J50. The Hamiltonian operator is given in collision coordinates. The Hamiltonian matrix elements are evaluated using symmetrized products of spherical harmonics for angles and a potential optimized discrete variable representation ~PO-DVR! for the ...

In this Letter, we present NMR spin-lattice and relaxometry data for proton transfer in one of the shortest known N-H⋯O hydrogen bonds in a single crystal of 3,5 pyridinedicarboxylic acid (35PDCA). It is widely believed that proton transfer by quantum tunneling does not occur in short hydrogen bonds since the ground state energy level lies above the potential barrier, yet these data show a temp...

It has been known for many years that the low temperature properties of amorphous solids below 1 K are dominated by the presence of tunneling states. This typical behavior can be described by the tunneling model [1]. However, above a few Kelvin the universal properties of glasses (plateau in the thermal conductivity; so-called boson peak) deviate from the predictions of the tunneling model. A s...

Supersonic jet-isolated porphycene (Pc) and its isotopomers have been studied using the techniques of laser induced fluorescence (LIF) excitation, single vibronic level fluorescence (SVLF) and hole burning spectroscopy, combined with quantum mechanical calculation of geometry and vibrational structures of the ground (S0) and lowest electronically excited (S1) states. Porphycene is a model for c...

Theoretical studies of hydrogen bond network rearrangement (HBNR) dynamics in liquid water have indicated that librational motions initiate the hydrogen bond breaking/formation processes. We present the results of using a simple time evolution method to extract and compare the tunneling lifetimes for motions that break and reform the hydrogen bond for the water dimer, trimer, and pentamer from ...

No-scale supersymmetry or gaugino mediation augmented with large negative Higgs soft masses at the input scale provides a simple solution to the supersymmetric flavor problem while giving rise to a neutralino LSP. However, to obtain a neutralino LSP it is often necessary to have tachyonic input Higgs soft masses that can give rise to chargeand-color-breaking (CCB) minima and unbounded-from-belo...

We present a theory of enzymatic hydrogen transfer in which hydrogen tunneling is mediated by thermal fluctuations of the enzyme's active site. These fluctuations greatly increase the tunneling rate by shortening the distance the hydrogen must tunnel. The average tunneling distance is shown to decrease when heavier isotopes are substituted for the hydrogen or when the temperature is increased, ...

Starting from the coherent state representation of the evolution operator with the help of the path–integral, we derive a formula for the low–lying levels E = ǫ0 − 2△ǫ cos(s+ ξ)π of a quantum spin system. The quenching of macroscopic quantum coherence is understood as the vanishing of cos(s+ ξ)π in disagreement with the suppression of tunneling (i.e. △ǫ = 0) as claimed in the literature. A new ...