25 research outputs found
Adsorption of CO on a Platinum (111) surface - a study within a four-component relativistic density functional approach
We report on results of a theoretical study of the adsorption process of a
single carbon oxide molecule on a Platinum (111) surface. A four-component
relativistic density functional method was applied to account for a proper
description of the strong relativistic effects. A limited number of atoms in
the framework of a cluster approach is used to describe the surface. Different
adsorption sites are investigated. We found that CO is preferably adsorbed at
the top position.Comment: 23 Pages with 4 figure
Gamma estimator of Jarzynski equality for recovering binding energies from noisy dynamic data sets
A fundamental problem in thermodynamics is the recovery of macroscopic equilibrated interaction energies from experimentally measured single-molecular interactions. The Jarzynski equality forms a theoretical basis in recovering the free energy difference between two states from exponentially averaged work performed to switch the states. In practice, the exponentially averaged work value is estimated as the mean of finite samples. Numerical simulations have shown that samples having thousands of measurements are not large enough for the mean to converge when the fluctuation of external work is above 4 kBT, which is easily observable in biomolecular interactions. We report the first example of a statistical gamma work distribution applied to single molecule pulling experiments. The Gibbs free energy of surface adsorption can be accurately evaluated even for a small sample size. The values obtained are comparable to those derived from multi-parametric surface plasmon resonance measurements and molecular dynamics simulations
Cluster-embedding method to simulate large cluster and surface problems
In order to describe processes which are localized on a surface or inside the
bulk of a solid, molecular calculations of an inner cluster may be adequate
as long as the effect of the outer environment is taken into account via an
embedding-method. Using a relativistic density functional method for the
self-consistent cluster calculation we have developed a new cluster-embedding
scheme here.
As an example we have studied the adsorption of Al on an Al(100) surface
and we get significant agreement with different methods. This indicates that this
embedding-method is reliable enough to simulate an unlimited solid
Verbal fluency deficits in patients with schizophrenia, psychotic bipolar disorder and their unaffected relatives
27th Congress of the European-College-of-Neuropsychopharmacology (ECNP) -- OCT 18-21, 2014 -- Berlin, GERMANYBastug, Gulbahar/0000-0002-8317-7711; Bastug, Gulbahar/0000-0002-8317-7711; OZEL-KIZIL, ERGUVAN TUGBA/0000-0001-9657-1382WOS: 000362851700203…European Coll Neuropsychopharmaco
Device-to-device data storage with regenerating codes
Caching data files directly on mobile user devices combined with device-to-device (D2D) communications has recently been suggested to improve the capacity of wireless networks. We investigate the performance of regenerating codes in terms of the total energy consumption of a cellular network. We show that regenerating codes can offer large performance gains. It turns out that using redundancy against storage node failures is only beneficial if the popularity of the data is between certain thresholds. As our major contribution, we investigate under which circumstances regenerating codes with multiple redundant data fragments outdo uncoded caching.Peer reviewe