4
4.0

Jun 30, 2018
06/18

by
A. A. Milner; A. Korobenko; J. W. Hepburn; V. Milner

texts

#
eye 4

#
favorite 0

#
comment 0

We use an optical centrifuge to excite coherent rotational wave packets in N$_2$O, CS$_2$ and OCS molecules with rotational quantum numbers reaching up to J=465, 690 and 1186, respectively. Time-resolved rotational spectroscopy at such ultra-high levels of rotational excitation can be used as a sensitive tool to probe the molecular potential energy surface at inter-nuclear distances far from their equilibrium values. Significant bond stretching in the centrifuged molecules results in the...

Topics: Physics, Chemical Physics

Source: http://arxiv.org/abs/1704.07504

14
14

Jun 28, 2018
06/18

by
A. A. Milner; A. Korobenko; V. Milner

texts

#
eye 14

#
favorite 0

#
comment 0

We introduce a new optical tool - a "two-dimensional optical centrifuge", capable of aligning molecules in extreme rotational states. Unlike the conventional centrifuge, which confines the molecules in the plane of their rotation, its two-dimensional version aligns the molecules along a well-defined axis, similarly to the effect of a single linearly polarized laser pulse, but at a much higher level of rotational excitation. The increased robustness of ultra-high rotational states with...

Topics: Quantum Physics, Chemical Physics, Physics

Source: http://arxiv.org/abs/1509.01891

17
17

Jun 26, 2018
06/18

by
A. A. Milner; A. Korobenko; V. Milner

texts

#
eye 17

#
favorite 0

#
comment 0

We use an optical centrifuge to deposit a controllable amount of rotational energy into dense molecular ensembles. Subsequent rotation-translation energy transfer, mediated by thermal collisions, results in the localized heating of the gas and generates strong sound wave, clearly audible to the unaided ear. For the first time, the amplitude of the sound signal is analyzed as a function of the experimentally measured rotational energy. The proportionality between the two experimental observables...

Topics: Chemical Physics, Physics, Optics

Source: http://arxiv.org/abs/1502.02654

29
29

Jun 28, 2018
06/18

by
A. B. Boyd; D. Mandal; J. P. Crutchfield

texts

#
eye 29

#
favorite 0

#
comment 0

We introduce a family of Maxwellian Demons for which correlations among information bearing degrees of freedom can be calculated exactly and in compact analytical form. This allows one to precisely determine Demon functional thermodynamic operating regimes, when previous methods either misclassify or simply fail due to approximations they invoke. This reveals that these Demons are more functional than previous candidates. They too behave either as engines, lifting a mass against gravity by...

Topics: Chemical Physics, Nonlinear Sciences, Statistical Mechanics, Physics, Condensed Matter, Biological...

Source: http://arxiv.org/abs/1507.01537

7
7.0

Jun 30, 2018
06/18

by
A. Bagci; P. E. Hoggan

texts

#
eye 7

#
favorite 0

#
comment 0

The use of Slater-type spinor orbitals in algebraic solution of the Dirac equation is investigated. The one- and two-center integrals constitute the matrix elements arising in generalized eigenvalue equation for one-electron atoms and molecules are evaluated over Slater-type spinor orbitals via ellipsoidal coordinates. These integrals are calculated through numerical global-adaptive method with Gauss-Kronrod numerical integration extension. The calculations are performed for electronic...

Topics: Physics, Chemical Physics, Atomic Physics

Source: http://arxiv.org/abs/1407.6720

11
11

Jun 27, 2018
06/18

by
A. Bagci; P. E. Hoggan

texts

#
eye 11

#
favorite 0

#
comment 0

The authors in their previous papers obtained compact, arbitrarily accurate expressions for two-center one- and two-electron relativistic molecular integrals expressed over Slater-type orbitals. In this present study, the accuracy limits of given expressions is examined for three-center nuclear attraction integrals, which are the first integral set do not have analytically closed form relations. They are expressed through new molecular auxiliary functions obtained via Neumann expansion of...

Topics: Chemical Physics, Mathematics, Physics, Mathematical Physics

Source: http://arxiv.org/abs/1503.03690

4
4.0

Jun 29, 2018
06/18

by
A. Benitez; C. R. Proetto

texts

#
eye 4

#
favorite 0

#
comment 0

Using a simplified one-dimensional model of a diatomic molecule, the associated interacting density and corresponding Kohn-Sham potential have been obtained analytically for all fractional molecule occupancies $N$ between 0 and 2. For the homonuclear case, and in the dissociation limit, the exact Kohn-Sham potential builds a barrier at the midpoint between the two atoms, whose strength increases linearly with $N$, with $1 < N \leq 2$. In the heteronuclear case, the disociating KS potential...

Topics: Atomic Physics, Chemical Physics, Physics

Source: http://arxiv.org/abs/1609.07674

3
3.0

Jun 30, 2018
06/18

by
A. Birczyński; Z. T. Lalowicz

texts

#
eye 3

#
favorite 0

#
comment 0

Our published and new experimental results by means of deuteron NMR spectroscopy in studies of molecular mobility in confinement are summarized and annalysed. Conclusions about limits of applicability of methods in disclosing several features are achieved. A set of molecules: D2, CD4, D2O, ND3, CD3OD and (CD3)2CO was chosen and introduced into zeolites with faujasite structure. Measurements of deuteron spectra and relaxation in function of loading and temperature provide a wealth of cases. A...

Topics: Physics, Chemical Physics

Source: http://arxiv.org/abs/1703.07850

4
4.0

Jun 28, 2018
06/18

by
A. Bravetti; D. Tapias

texts

#
eye 4

#
favorite 0

#
comment 0

We present a deterministic algorithm called contact density dynamics that generates any prescribed target distribution in the physical phase space. Akin to the famous model of Nos\'e-Hoover, our algorithm is based on a non-Hamiltonian system in an extended phase space. However the equations of motion in our case follow from contact geometry and we show that in general they have a similar form to those of the so-called density dynamics algorithm. As a prototypical example, we apply our algorithm...

Topics: Statistical Mechanics, Mathematics, Condensed Matter, Mathematical Physics, Physics, Chemical...

Source: http://arxiv.org/abs/1510.03942

3
3.0

Jun 28, 2018
06/18

by
A. C. LaForge; D. Regina; G. Jabbari; K. Gokhberg; N. V. Kryzhevoi; S. R. Krishnan; M. Hess; P. O'Keeffe; A. Ciavardini; K. C. Prince; R. Richter; R. Moshammer; L. S. Cederbaum; T. Pfeifer; F. Stienkemeier; M. Mudrich

texts

#
eye 3

#
favorite 0

#
comment 0

Doubly-excited Rydberg states of helium (He) nanodroplets have been studied using synchrotron radiation. We observed Fano resonances related to the atomic N = 2,0 series as a function of droplet size. Although similar qualitatively to their atomic counterparts, the resonance lines are broader and exhibit a shift in energy which increases for the higher excited states. Furthermore, additional resonances are observed which are not seen in atomic systems. We discuss these features in terms of...

Topics: Atomic and Molecular Clusters, Chemical Physics, Physics

Source: http://arxiv.org/abs/1510.05473

23
23

Jun 28, 2018
06/18

by
A. C. LaForge; V. Stumpf; K. Gokhberg; J. von Vangerow; N. V. Kryzhevoi; P. O'Keeffe; A. Ciavardini; S. R. Krishnan; M. Coreno; K. C. Prince; R. Richter; R. Moshammer; T. Pfeifer; L. S. Cederbaum; F. Stienkemeier; M. Mudrich

texts

#
eye 23

#
favorite 0

#
comment 0

Here, we report the observation of electron transfer mediated decay (ETMD) involving Mg clusters embedded in helium nanodroplets which is initiated by the ionization of helium followed by removal of two electrons from the Mg clusters of which one is transferred to the He environment neutralizing it while the other electron is emitted into the continuum. The process is shown to be the dominant ionization mechanism for embedded clusters for photon energies above the ionization potential of He....

Topics: Chemical Physics, Physics, Atomic and Molecular Clusters

Source: http://arxiv.org/abs/1509.04569

20
20

Jun 28, 2018
06/18

by
A. C. Maggs; R. Podgornik

texts

#
eye 20

#
favorite 0

#
comment 0

We study the Poisson-Boltzmann equation in the context of dense charged fluids where steric effects become important. We generalise the lattice gas theory by introducing a Flory-Huggins entropy for ions of differing volumes and then compare the effective free energy density to other approximations, valid for more realistic equations of state, such as the Carnahan-Starling approximation and find strong differences in the shapes of the free energy functions. We solve the Carnahan-Starling model...

Topics: Chemical Physics, Physics, Condensed Matter, Soft Condensed Matter

Source: http://arxiv.org/abs/1507.04533

3
3.0

Jun 30, 2018
06/18

by
A. Candian; P. J. Sarre; A. G. G. M. Tielens

texts

#
eye 3

#
favorite 0

#
comment 0

In this Letter we report the results of density functional theory calculations on medium-sized neutral Polycyclic Aromatic Hydrocarbon (PAH) molecules with armchair edges. These PAH molecules possess strong C-H stretching and bending modes around 3 {\mu}m and in the fingerprint region (10-15 {\mu}m), and also strong ring deformation modes around 12.7 {\mu}m. Perusal of the entries in the NASA Ames PAHs Database shows that ring deformation modes of PAHs are common - although generally weak. We...

Topics: Physics, Chemical Physics, Astrophysics of Galaxies, Astrophysics

Source: http://arxiv.org/abs/1407.2010

5
5.0

Jun 29, 2018
06/18

by
A. Celestino; A. Eisfeld

texts

#
eye 5

#
favorite 0

#
comment 0

We show that molecular aggregation can strongly influence the nonradiative decay (NRD) lifetime of an electronic excitation. As a demonstrative example, we consider a transition-dipole-dipole-interacting dimer whose monomers have harmonic potential energy surfaces (PESs). Depending on the position of the NRD channel ($q_{\rm nr}$), we find that the NRD lifetime ($\tau_{\rm nr}^{\rm dim}$) can exhibit a completely different dependence on the intermolecular-interaction strength. We observe that...

Topics: Chemical Physics, Physics

Source: http://arxiv.org/abs/1611.09115

3
3.0

Jun 30, 2018
06/18

by
A. D. Kudashov; A. N. Petrov; L. V. Skripnikov; N. S. Mosyagin; T. A. Isaev; R. Berger; A. V. Titov

texts

#
eye 3

#
favorite 0

#
comment 0

Relativistic ab initio calculations have been performed to assess the suitability of RaF for experimental search of P- and T,P-violating interactions. The parameters of P- and T,P-odd terms of the spin-rotational Hamiltonian have been calculated for the ${^2}\Sigma$ electronic ground state of RaF molecule. They include the parameter $W_a$, which is critical in experimental search for nuclear anapole moment and the parameters $W_d$ and $W_{\rm SP}$ required to obtain restrictions on the electric...

Topics: Physics, Chemical Physics, Atomic Physics, Quantum Physics

Source: http://arxiv.org/abs/1405.6391

17
17

Jun 30, 2018
06/18

by
A. E. Gheribi; D. Corradini; L. Dewan; P. Chartrand; C. Simon; P. A. Madden; M. Salanne

texts

#
eye 17

#
favorite 0

#
comment 0

Molten fluorides are known to show favorable thermophysical properties which make them good candidate coolants for nuclear fission reactors. Here we investigate the special case of mixtures of lithium fluoride and thorium fluoride, which act both as coolant and fuel in the molten salt fast reactor concept. By using ab initio parameterized polarizable force fields, we show that it is possible to calculate the whole set of properties (density, thermal expansion, heat capacity, viscosity and...

Topics: Physics, Chemical Physics, Materials Science, Condensed Matter

Source: http://arxiv.org/abs/1402.4237

5
5.0

Jun 29, 2018
06/18

by
A. E. Kuchma; A. K. Shchekin; D. S. Martyukova

texts

#
eye 5

#
favorite 0

#
comment 0

A new comprehensive analysis of Stefan's flow caused by a free growing droplet in vapor-gas atmosphere with several condensing components is presented. This analysis, based on the nonstationary heat and material balance and diffusion transport equations, shows the appearance of the Stefan inflow in the vicinity of the growing droplet and the outflow at large distances from the droplet as a consequence of nonisothermal condensation. For an ensemble of droplets in the atmospheric cloud, this flow...

Topics: Soft Condensed Matter, Chemical Physics, Condensed Matter, Atmospheric and Oceanic Physics, Physics

Source: http://arxiv.org/abs/1606.02086

7
7.0

Jun 30, 2018
06/18

by
A. E. Sitnitsky

texts

#
eye 7

#
favorite 0

#
comment 0

We construct a double-well potential for which the Schr\"odinger equation can be exactly solved via reducing to the confluent Heun's one. Thus the wave function is expressed via the confluent Heun's function. The latter is tabulated in {\sl {Maple}} so that the obtained solution is easily treated. The potential is infinite at the boundaries of the final interval that makes it to be highly suitable for modeling hydrogen bonds (both ordinary and low-barrier ones). We exemplify theoretical...

Topics: Physics, Mesoscale and Nanoscale Physics, Condensed Matter, Chemical Physics

Source: http://arxiv.org/abs/1703.00007

4
4.0

Jun 29, 2018
06/18

by
A. Faure; F. Lique; L. Wiesenfeld

texts

#
eye 4

#
favorite 0

#
comment 0

New calculations for rotational excitation of cyanoacetylene by collisions with hydrogen molecules are performed to include the lowest 38 rotational levels of HC3N and kinetic temperatures to 300 K. Calculations are based on the interaction potential of Wernli et al. A&A, 464, 1147 (2007) whose accuracy is checked against spectroscopic measurements of the HC3N-H2 complex. The quantum coupled-channel approach is employed and complemented by quasi-classical trajectory calculations. Rate...

Topics: Astrophysics, Chemical Physics, Astrophysics of Galaxies, Physics

Source: http://arxiv.org/abs/1605.03786

3
3.0

Jun 30, 2018
06/18

by
A. Ferré; A. E. Boguslavskiy; M. Dagan; V. Blanchet; B. Bruner; F. Burgy; A. Camper; D. Descamps; B. Fabre; N. Fedorov; J. Gaudin; G. Geoffroy; J. Mikosch; S. Patchkovskii; S. Petit; T. Ruchon; H. Soifer; D. Staedter; I. Wilkinson; A. Stolow; N. Dudovich; Y. Mairesse

texts

#
eye 3

#
favorite 0

#
comment 0

High-order harmonic generation in polyatomic molecules generally involves multiple channels, each associated with a different orbital. Their unambiguous assignment remains a major challenge for high-harmonic spectroscopy. Here we present a multi-modal approach, using unaligned SF$_6$ molecules as an example, where we combine methods from extreme-ultraviolet spectroscopy, above-threshold ionization and attosecond metrology. Channel-resolved above-threshold ionization measurements reveal that...

Topics: Physics, Chemical Physics, Atomic Physics

Source: http://arxiv.org/abs/1407.6213

6
6.0

Jun 29, 2018
06/18

by
A. Hanusch; J. Rapp; M. Brics; D. Bauer

texts

#
eye 6

#
favorite 0

#
comment 0

Recently introduced time-dependent renormalized-natural orbital theory (TDRNOT) is extended towards a multi-component approach in order to describe H$_2^+$ beyond the Born-Oppenheimer approximation. Two kinds of natural orbitals, describing the electronic and the nuclear degrees of freedom are introduced, and the exact equations of motion for them are derived. The theory is benchmarked by comparing numerically exact results of the time-dependent Schr\"odinger equation for a H$_2^+$ model...

Topics: Chemical Physics, Physics, Computational Physics

Source: http://arxiv.org/abs/1602.02104

8
8.0

Jun 28, 2018
06/18

by
A. Hashemloo; C. M. Dion

texts

#
eye 8

#
favorite 0

#
comment 0

We present models for a heteronuclear diatomic molecular ion in a linear Paul trap in a rigid-rotor approximation, one purely classical, the other where the center-of-mass motion is treated classically while rotational motion is quantized. We study the rotational dynamics and their influence on the motion of the center-of-mass, in the presence of the coupling between the permanent dipole moment of the ion and the trapping electric field. We show that the presence of the permanent dipole moment...

Topics: Chemical Physics, Atomic Physics, Physics

Source: http://arxiv.org/abs/1511.04114

4
4.0

Jun 30, 2018
06/18

by
A. I. Pavlyuchko; S. N. Yurchenko; Jonathan Tennyson

texts

#
eye 4

#
favorite 0

#
comment 0

A procedure for calculation of rotation-vibration states of medium sized molecules is presented. It combines the advantages of variational calculations and perturbation theory. The vibrational problem is solved by diagonalizing a Hamiltonian matrix, which is partitioned into two sub-blocks. The first, smaller sub-block includes matrix elements with the largest contribution to the energy levels targeted in the calculations. The second, larger sub-block comprises those basis states which have...

Topics: Physics, Chemical Physics, Atmospheric and Oceanic Physics

Source: http://arxiv.org/abs/1411.6098

3
3.0

Jun 30, 2018
06/18

by
A. I. Pavlyuchko; S. N. Yurchenko; Jonathan Tennyson

texts

#
eye 3

#
favorite 0

#
comment 0

Rotation-vibration spectra of the nitric acid molecule, HNO\3, are calculated for wavenumbers up to 7000~\cm. Calculations are performed using a Hamiltonian expressed in internal curvilinear vibrational coordinates solved using a hybrid variational-perturbation method. An initial potential energy surface (PES) and dipole moment function (DMF) are calculated {\it ab initio} at the CCSD(T)/aug-cc-pVQZ level of theory. Parameters of the PES and DMF are varied to minimize differences between the...

Topics: Physics, Chemical Physics

Source: http://arxiv.org/abs/1412.6744

9
9.0

Jun 29, 2018
06/18

by
A. I. Shushin

texts

#
eye 9

#
favorite 0

#
comment 0

The work concerns the analysis of experimental time-resolved ESR spectra in photoexcited polymer:fullerene blend, consisting of poly(3-hexilthiophene) and fullerene [6,6]-phenyl C_{61} -butyric acid methyl ester (at low temperature T = 100 K). The spectra are assumed to be determined by spin-coherent pairs of charged polarons P^{+} and P^{-} generated in the singlet state. The analysis is made within simple model of a set of first order processes, in which P^{+}P$^{-}-pair spin evolution is...

Topics: Chemical Physics, Materials Science, Condensed Matter, Physics

Source: http://arxiv.org/abs/1611.07286

5
5.0

Jun 30, 2018
06/18

by
A. J. de Nijs; W. Ubachs; H. L. Bethlem

texts

#
eye 5

#
favorite 0

#
comment 0

Using a Ramsey-type setup, the lambda-doublet transition in the $J=1,\, \Omega=1$ level of the $a^3\Pi$ state of CO was measured to be 394 064 870(10) Hz. In our molecular beam apparatus, a beam of metastable CO is prepared in a single quantum level by expanding CO into vacuum and exciting the molecules using a narrow-band UV laser system. After passing two microwave zones that are separated by 50 cm, the molecules are state-selectively deflected and detected 1 meter downstream on a position...

Topics: Physics, Chemical Physics, Atomic Physics

Source: http://arxiv.org/abs/1405.2740

3
3.0

Jun 30, 2018
06/18

by
A. Jiménez-Escobar; B. M. Giuliano; G. M. Muñoz Caro; J. Cernicharo; N. Marcelino

texts

#
eye 3

#
favorite 0

#
comment 0

Current gas phase models do not account for the abundances of HNCO isomers detected in various environments, suggesting a formation in icy grain mantles. We attempted to study a formation channel of HNCO and its possible isomers by vacuum-UV photoprocessing of interstellar ice analogues containing H$_2$O, NH$_3$, CO, HCN, CH$_3$OH, CH$_4$, and N$_2$ followed by warm-up, under astrophysically relevant conditions. Only the H$_2$O:NH$_3$:CO and H$_2$O:HCN ice mixtures led to the production of HNCO...

Topics: Physics, Instrumentation and Methods for Astrophysics, Chemical Physics, Astrophysics of Galaxies,...

Source: http://arxiv.org/abs/1407.1242

16
16

Jun 27, 2018
06/18

by
A. K. Bhattacharjee; K. Balakrishnan; A. L. Garcia; J. B. Bell; A. Donev

texts

#
eye 16

#
favorite 0

#
comment 0

We formulate and study computationally the fluctuating compressible Navier-Stokes equations for reactive multi-species fluid mixtures. We contrast two different expressions for the covariance of the stochastic chemical production rate in the Langevin formulation of stochastic chemistry, and compare both of them to predictions of the chemical Master Equation for homogeneous well-mixed systems close to and far from thermodynamic equilibrium. We develop a numerical scheme for inhomogeneous...

Topics: Fluid Dynamics, Chemical Physics, Physics

Source: http://arxiv.org/abs/1503.07478

6
6.0

Jun 30, 2018
06/18

by
A. Kievsky; N. K. Timofeyuk; M. Gattobigio

texts

#
eye 6

#
favorite 0

#
comment 0

We present the analysis of the $N$-boson spectrum computed using a soft two-body potential the strength of which has been varied in order to cover an extended range of positive and negative values of the two-body scattering length $a$ close to the unitary limit. The spectrum shows a tree structure of two states, one shallow and one deep, attached to the ground-state of the system with one less particle. It is governed by an unique universal function, $\Delta(\xi)$, already known in the case of...

Topics: Physics, Quantum Physics, Quantum Gases, Atomic and Molecular Clusters, Chemical Physics, Nuclear...

Source: http://arxiv.org/abs/1405.2371

8
8.0

Jun 28, 2018
06/18

by
A. Korobenko; V. Milner

texts

#
eye 8

#
favorite 0

#
comment 0

We use an optical centrifuge to align asymmetric top $\mathrm{SO_2}$ molecules by adiabatically spinning their most polarizable O-O axis. The effective centrifugal potential in the rotating frame confines sulfur atoms to the plane of the laser-induced rotation, leading to the planar molecular alignment which persists after the molecules are released from the centrifuge. Periodic appearance of the full three-dimensional alignment, typically observed only with linear and symmetric top molecules,...

Topics: Chemical Physics, Physics

Source: http://arxiv.org/abs/1510.01827

3
3.0

Jun 30, 2018
06/18

by
A. L. Khomkin; A. S. Shumikhin

texts

#
eye 3

#
favorite 0

#
comment 0

High values of deuterium compressibility under shock-wave compression, recently discovered in several experiments, are explained by an unusual dielectric-metal phase transition from a dense molecular gas into a liquid-metal atomic gas. This phase transition recently described by authors was named the dissociative phase transition (DPT). The same phase transition describes a significant scattering of experimentally measured densities within an area of anomalous compressibility.

Topics: Physics, Chemical Physics, Plasma Physics

Source: http://arxiv.org/abs/1408.2753

4
4.0

Jun 29, 2018
06/18

by
A. Lindmaa; R. Armiento

texts

#
eye 4

#
favorite 0

#
comment 0

The recent non-empirical semi-local exchange functional of Armiento and K\"ummel, the AK13 [PRL 111, 036402 (2013)] incorporates a number of features reproduced by higher-order theory. The AK13 potential behaves analogously with the discontinuous jump associated with the derivative discontinuity at integer particle numbers. Recent works have established that AK13 gives a qualitatively improved orbital description compared to other semi-local methods, and reproduces a band structure closer...

Topics: Chemical Physics, Condensed Matter, Physics, Other Condensed Matter

Source: http://arxiv.org/abs/1604.01957

10
10.0

Jun 28, 2018
06/18

by
A. M. P. Mendez; D. M. Mitnik; J. E. Miraglia

texts

#
eye 10

#
favorite 0

#
comment 0

This work presents exchange potentials for specific orbitals calculated by inverting Hartree-Fock wavefunctions. This was achieved by using a Depurated Inversion Method. The basic idea of the method relies upon the substitution of Hartree-Fock orbitals and eigenvalues into the Kohn-Sham equation. Through inversion, the corresponding effective potentials were obtained. Further treatment of the inverted potential should be carried on. The depuration is a careful optimization which eliminates the...

Topics: Chemical Physics, Physics, Atomic and Molecular Clusters

Source: http://arxiv.org/abs/1509.02161

18
18

Jun 27, 2018
06/18

by
A. M. Ramos; C. P. Please

texts

#
eye 18

#
favorite 0

#
comment 0

In this article the Butler-Volmer equation used in describing Lithium-ion (Li-ion) batteries is discussed. First, a complete mathematical model based on a macro-homogeneous approach developed by Neuman is presented. Two common mistakes found in the literature regarding a sign in a boundary conditions and the use of the transfer coefficient are mentioned. The paper focuses on the form of the Butler-Volmer equation in the model. It is shown how practical problems can be avoided by taking care in...

Topics: Chemical Physics, Physics

Source: http://arxiv.org/abs/1503.05912

4
4.0

Jun 29, 2018
06/18

by
A. Maslechko; K. Glavatskiy; V. Kulinskii

texts

#
eye 4

#
favorite 0

#
comment 0

The approach of global isomorphism between the fluid and the Ising model is applied to obtain an expression for the surface tension of the Lennard-Jones fluid on the basis of the information about the Ising model. This is done in a broad interval of temperatures along the phase coexistence, and is valid both in 2D and 3D. The relation between the critical amplitudes of the surface tension of the fluid and the Ising model is derived in the vicinity of the critical point. The obtained theoretical...

Topics: Soft Condensed Matter, Chemical Physics, Condensed Matter, Physics

Source: http://arxiv.org/abs/1608.05136

5
5.0

Jun 28, 2018
06/18

by
A. Mielke; M. A. Peletier; D. R. M. Renger

texts

#
eye 5

#
favorite 0

#
comment 0

Onsager's 1931 `reciprocity relations' result connects microscopic time-reversibility with a symmetry property of corresponding macroscopic evolution equations. Among the many consequences is a variational characterization of the macroscopic evolution equation as a gradient-flow, steepest-ascent, or maximal-entropy-production equation. Onsager's original theorem is limited to close-to-equilibrium situations, with a Gaussian invariant measure and a linear macroscopic evolution. In this paper we...

Topics: Statistical Mechanics, Condensed Matter, Mathematics, Physics, Dynamical Systems, Probability,...

Source: http://arxiv.org/abs/1510.06219

8
8.0

Jun 30, 2018
06/18

by
A. Mokhberi; S. Willitsch

texts

#
eye 8

#
favorite 0

#
comment 0

We report the sympathetic cooling and Coulomb crystallization of molecular ions above the surface of an ion-trap chip. N$_2^+$ and CaH$^+$ ions were confined in a surface-electrode radiofrequency ion trap and cooled by the interaction with laser-cooled Ca$^{+}$ ions to secular translational temperatures in the millikelvin range. The configuration of trapping potentials generated by the surface electrodes enabled the formation of planar bicomponent Coulomb crystals and the spatial separation of...

Topics: Physics, Chemical Physics, Atomic Physics

Source: http://arxiv.org/abs/1404.4292

11
11

Jun 27, 2018
06/18

by
A. N. Gorban; V. N. Kolokoltsov

texts

#
eye 11

#
favorite 0

#
comment 0

The nonlinear Markov processes are the measure-valued dynamical systems which preserve positivity. They can be represented as the law of large numbers limits of general Markov models of interacting particles. In physics, the kinetic equations allow Lyapunov functionals (entropy, free energy, etc.). This may be considered as a sort of inheritance of the Lyapunov functionals from the microscopic master equations. We study nonlinear Markov processes that inherit thermodynamic properties from the...

Topics: Condensed Matter, Statistical Mechanics, Chemical Physics, Physics

Source: http://arxiv.org/abs/1504.08317

16
16

Jun 27, 2018
06/18

by
A. P. Furlan; Carlos E. Fiore; M. C. Barbosa

texts

#
eye 16

#
favorite 0

#
comment 0

The thermodynamic, dynamic and structural behavior of a water-like system confined in a matrix is analyzed for increasing confining geometries. The liquid is modeled by a two dimensional associating lattice gas model that exhibits density and diffusion anomalies, in similarity to the anomalies present in liquid water. The matrix is a triangular lattice in which fixed obstacles impose restrictions to the occupation of the particles. We show that obstacules shortens all lines, including the phase...

Topics: Condensed Matter, Statistical Mechanics, Soft Condensed Matter, Chemical Physics, Physics

Source: http://arxiv.org/abs/1504.04608

3
3.0

Jun 29, 2018
06/18

by
A. Patrykiejew; T. Staszewski

texts

#
eye 3

#
favorite 0

#
comment 0

In this paper we have considered a simple lattice gas model of chemisorbed monolayer which allows for the harmonic fluctuations of the bond length between the adsorbate atom and the surface site. The model also involves a short-ranged attractive potential acting between the adsorbed atoms as well as the surface periodic corrugation potential. It has been assumed that the adsorbed atoms are bonded to the uppermost layer of the substrate atoms. In particular, using Monte Carlo simulation method...

Topics: Mesoscale and Nanoscale Physics, Chemical Physics, Condensed Matter, Physics

Source: http://arxiv.org/abs/1603.02047

4
4.0

Jun 30, 2018
06/18

by
A. Perveaux; D. Lauvergnat; B. Lasorne; F. Gatti; M. A. Robb; G. J. Halász; Á. Vibók

texts

#
eye 4

#
favorite 0

#
comment 0

A nonadiabatic scheme for the description of the coupled electron and nuclear motions in the ozone molecule was proposed recently. An initial coherent nonstationary state was prepared as a superposition of the ground state and the excited Hartley band. In this situation neither the electrons nor the nuclei are in a stationary state. The multiconfiguration time dependent Hartree method was used to solve the coupled nuclear quantum dynamics in the framework of the adiabatic separation of the...

Topics: Physics, Chemical Physics, Atomic and Molecular Clusters

Source: http://arxiv.org/abs/1401.6927

13
13

Jun 26, 2018
06/18

by
A. Ruderman; A. D. Dente; E. Santos; H. M. Pastawski

texts

#
eye 13

#
favorite 0

#
comment 0

In this work we show that the molecular chemical bond formation and dissociation in presence of the d-band of a metal catalyst can be described as a Quantum Dynamical Phase Transition (QDPT). This agree with DFT calculations that predict sudden jumps in some observables as the molecule breaks. According to our model this phenomenon emerges because the catalyst provides for a non- Hermitian Hamiltonian. We show that when the molecule approaches the surface, as occurs in the Heyrovsky reaction of...

Topics: Chemical Physics, Physics, Quantum Physics

Source: http://arxiv.org/abs/1502.02048

22
22

Jun 27, 2018
06/18

by
A. S. Nikolaev

texts

#
eye 22

#
favorite 0

#
comment 0

This work establishes a connection between canonical perturbation series in quantum mechanics and a Kato expansion for the resolvent of the Liouville superoperator. Our approach leads to an explicit expression for a generator of a block-diagonalizing Dyson's ordered exponential in arbitrary perturbation order. Unitary intertwining of perturbed and unperturbed averaging superprojectors allows for a description of ambiguities in the generator and block-diagonalized Hamiltonian. We compare the...

Topics: Quantum Physics, Chemical Physics, Mathematics, Physics, Mathematical Physics

Source: http://arxiv.org/abs/1504.05113

4
4.0

Jun 30, 2018
06/18

by
A. S. Sanz

texts

#
eye 4

#
favorite 0

#
comment 0

Effective descriptions accounting for the evolution of quantum systems that are acted on by a bath are desirable. As the number of bath degrees of freedom increases and full quantum simulations turn out computationally prohibitive, simpler models become essential to understand and gain an insight into the main physical mechanisms involved in the system dynamics. In this regard, vibrational decoherence of an I$_2$ diatomics is tackled here within the framework of Markovian quantum state...

Topics: Quantum Physics, Chemical Physics, Physics, Computational Physics

Source: http://arxiv.org/abs/1402.3878

5
5.0

Jun 30, 2018
06/18

by
A. S. Sanz; M. Davidovic; M. Bozic

texts

#
eye 5

#
favorite 0

#
comment 0

Atomic three-grating Mach-Zehnder interferometry constitutes an important tool to probe fundamental aspects of the quantum theory. There is, however, a remarkable gap in the literature between the oversimplified models and robust numerical simulations considered to describe the corresponding experiments. Consequently, the former usually lead to paradoxical scenarios, such as the wave-particle dual behavior of atoms, while the latter make difficult the data analysis in simple terms. Here these...

Topics: Physics, Chemical Physics, Atomic Physics, Quantum Physics, Optics

Source: http://arxiv.org/abs/1402.3885

3
3.0

Jun 30, 2018
06/18

by
A. Scemama; T. Applencourt; E. Giner; M. Caffarel

texts

#
eye 3

#
favorite 0

#
comment 0

We present accurate nonrelativistic ground-state energies of the transition metal atoms of the 3d series calculated with Fixed-Node Diffusion Monte Carlo (FN-DMC). Selected multi-determinantal expansions obtained with the CIPSI method (Configuration Interaction using a Perturbative Selection made Iteratively) and including the most prominent determinants of the full CI expansion are used as trial wavefunctions. Using a maximum of a few tens of thousands determinants, fixed-node errors on total...

Topics: Physics, Chemical Physics

Source: http://arxiv.org/abs/1409.3671

5
5.0

Jun 30, 2018
06/18

by
A. Shabani; M. Mohseni; H. Rabitz.; S. Lloyd

texts

#
eye 5

#
favorite 0

#
comment 0

Recent theoretical studies show that decoherence process can enhance transport efficiency in quantum systems. This effect is known as environment-assisted quantum transport (ENAQT). The role of ENAQT in optimal quantum transport is well investigated, however, it is less known how robust ENAQT is with respect to variations in the system or its environment characteristic. Toward answering this question, we simulated excitonic energy transfer in Fenna-Matthews-Olson (FMO) photosynthetic complex....

Topics: Quantum Physics, Physics, Chemical Physics, Mesoscale and Nanoscale Physics, Biological Physics,...

Source: http://arxiv.org/abs/1405.2623

3
3.0

Jun 30, 2018
06/18

by
A. Thilagam

texts

#
eye 3

#
favorite 0

#
comment 0

Optical devices fabricated using conjugated polymer systems give rise to singlet exciton yields which are high compared to the statistically predicted estimate of 25% obtained using simple recombination schemes. In this study we evaluate the singlet exciton yield in conjugated polymers systems by fitting to a model that incorporates the Pauli exclusion principle. The rate equations which describe the exciton dynamics include quantum dynamical components (both density and spin-dependent) which...

Topics: Physics, Chemical Physics, Materials Science, Condensed Matter

Source: http://arxiv.org/abs/1411.5185

27
27

Jun 28, 2018
06/18

by
A. V. Mitin

texts

#
eye 27

#
favorite 0

#
comment 0

The full analytical solution of the Schr\"{o}dinger equation for the hydrogen molecular ion $H_2^+$ (special case of the quantum tree-body problem with the Coulomb interaction) is obtained first. The solution shows that the total wave function is a two-term function in the sense that it is a linear combination of the two linear independent wave functions. The two-term character of the total wave function was visualized in calculations of the total electron density of $H_2^+$ at different...

Topics: Quantum Physics, Chemical Physics, Atomic Physics, Physics

Source: http://arxiv.org/abs/1508.01359

16
16

Jun 28, 2018
06/18

by
A. Widom; J. Swain; Y. N. Srivastava

texts

#
eye 16

#
favorite 0

#
comment 0

Electron transfer organic reaction rates are considered employing the classic physical picture of Marcus wherein the heats of reaction are deposited as the energy of low frequency mechanical oscillations of reconfigured molecular positions. If such electron transfer chemical reaction events occur in the neighborhood of metallic plates, then electrodynamic interface fields must also be considered in addition to mechanical oscillations. Such electrodynamic interfacial electric fields in principle...

Topics: Chemical Physics, Physics

Source: http://arxiv.org/abs/1508.00855