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The Ar(3) system has been studied between T=0 K and T=40 K by means of a path-integral Monte Carlo (PIMC) method. The behavior of the average energy in terms of the temperature has been explained by comparison with results obtained with the thermal averaged rovibrational spectra estimated via: (i) a quantum mechanical method based on distributed Gaussian(More)
Helium trimer bound states are calculated by means of a variational method described in terms of atom pair coordinates and distributed Gaussian basis functions for zero total angular momentum. To show the feasibility of this method, we also apply it to the calculation of the first vibrational levels of the Ar3 and Ne3 clusters. Special emphasis is made on(More)
From a string theory point of view the most natural gauge action on the fuzzy sphere S 2 L is the Alekseev-Recknagel-Schomerus action which is a particular combination of the Yang-Mills action and the Chern-Simons term. The differential calculus on the fuzzy sphere is 3−dimensional and thus the field content of this model consists of a 2-dimensional gauge(More)
An approximation to the Fourier transform (FT) of the Kohlrausch function (stretched exponential) with shape parameter 0 < β ≤ 1 is presented by using Havriliak-Negami-like functions. Mathematical expressions to fit their parameters α, γ, and τ, as functions of β (0 < β ≤ 1 and 1 < β < 2) are given, which allows a quick identification in the frequency(More)
We compute the one-loop effective potential for noncommutative U (1) gauge fields on S 2 L ×S 2 L. We show the existence of a novel phase transition in the model from the 4−dimensional space S 2 L ×S 2 L to a matrix phase where the spheres collapse under the effect of quantum fluctuations. It is also shown that the transition to the matrix phase occurs at(More)
Yeasts colonizing the Antarctic region are exposed to a high ultraviolet radiation evolving mechanisms to minimize the UV radiation damages, such as the production of UV-absorbing or antioxidant compounds like carotenoid pigments and mycosporines. Ergosterol has also been suggested to play a role in this response. These compounds are also economically(More)
A new embedding method to include local correlation in large systems is proposed. In this method the density of the whole system, calculated via density functional theory approaches, is partitioned in two pieces, one corresponding to the subsystem of interest and the rest to the environment. In the second step, an embedding potential is obtained iteratively(More)
The full sequence of the bound states for a very floppy triatomic complex, Ne2H- in its ground electronic state, are initially computed for the rotationless situation and employing a variational approach that expands the total nuclear wave function over a large set of symmetry-adapted, distributed Gaussian functions and employs accurate atom-atom potential(More)
In this review we report on interaction potential surface calculations of Rg–XY (Rg = rare gas and X, Y = halogens) van der Waals (vdW) complexes. Experimental data available on the structure and dynamics of such systems mainly originate from the B← X excitation spectroscopy and, therefore, potential surfaces for both electronic states involved are required(More)
A recently developed quantum-chemistry-like methodology to study molecules solvated in atomic clusters is applied to the ICl (iodine chloride) polar diatomic molecule immersed in clusters of He atoms. The atoms of the solvent clusters are treated as the ‘electrons’ and the solvated molecule as a structured ‘nucleus’ of the combined solvent-solute system.(More)