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Related papers: Solid molecular hydrogen: The Broken Symmetry Phas…

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Accurate experimental values for the vibrational ground tone or fundamental vibrational energy splitting of H$_2$, HD, and D$_2$ are presented. Absolute accuracies of $2\times10^{-4}$ cm$^{-1}$ are obtained from Doppler-free laser…

A calculation of the rotational S$_0$(0) frequencies in high pressure solid para-hydrogen is performed. Convergence of the perturbative series at high density is demonstrated by the calculation of second and third order terms. The results…

Statistical Mechanics · Physics 2009-11-10 Francesco Grazzi , Massimo Moraldi , Lorenzo Ulivi

The hybrid Stimulated Raman Scattering - Two Plasmon Decay instability had shown to play the dominant role for plasma waves excitation and energy absorption at interaction of very intense femtosecond obliquely incident $p$-polarized laser…

Plasma Physics · Physics 2021-01-04 I. Tsymbalov , D. Gorlova , A. Savel'ev

We have studied solid hydrogen up to pressures of 300 GPa and temperatures of 350 K using density functional theory methods and have found "mixed structures" that are more stable than those predicted earlier. Mixed structures consist of…

Materials Science · Physics 2012-06-20 Chris J. Pickard , Miguel Martinez-Canales , Richard J. Needs

The ground and excited vibrational states for the three hydrogen isotopes on the Pd(111) surface have been calculated. Notable features of these states are the high degree of anharmonicity, which is most prominently seen in the weak…

chem-ph · Physics 2009-10-22 Steven W. Rick , J. D. Doll

Since the 1985 discovery of the phase transition at $T_{\rm HO}=17.5$ K in the heavy-fermion metal URu$_2$Si$_2$, neither symmetry change in the crystal structure nor magnetic ordering have been observed, which makes this "hidden order"…

In this paper we report a new high-pressure rhombohedral phase of Ce2Zr2O8 observed from high-pressure angle-dispersive x-ray diffraction and Raman spectroscopy studies up to nearly 12 GPa. The ambient-pressure cubic phase of Ce2Zr2O8…

Materials Science · Physics 2012-03-12 D. Errandonea , R. S. Kumar , S. N. Achary , O. Gomis , F. J. Manjon , R. Shukla , A. K. Tyagi

We study spontaneous symmetry breaking in a one-dimensional driven two-species stochastic cellular automaton with parallel sublattice update and open boundaries. The dynamics are symmetric with respect to interchange of particles. Starting…

Statistical Mechanics · Physics 2009-11-11 Stefan Grosskinsky , Gunter M. Schutz , Richard D. Willmann

We present high-precision non-relativistic variational calculations of bound vibrational-rotational state energies for the $H_2^+$ and $D_2^+$ molecular ions in each of the lowest electronic states of $\Sigma_g$, $\Sigma_u$, and $\Pi_u$…

Atomic Physics · Physics 2007-05-23 J. M. Taylor , Zong-Chao Yan , A. Dalgarno , J. F. Babb

Molecular dynamics is a powerful method for studying the behaviour of materials at high temperature. In practice, however, its effectiveness in representing real systems is limited by the accuracy of the forces, finite size effects,…

Materials Science · Physics 2016-06-14 Graeme J Ackland , Ioan B Magdău

We present an accurate computational study of the electronic structure and lattice dynamics of solid molecular hydrogen at high pressure. The band-gap energies of the $C2/c$, $Pc$, and $P6_3/m$ structures at pressures of 250, 300, and 350…

Materials Science · Physics 2017-10-27 Sam Azadi , Ranber Singh , T. D. Kühne

An effective Hamiltonian without symmetry restriction has been developed to model the rotational and fine structure of two nearly degenerate electronic states of an open-shell molecule. In addition to the rotational Hamiltonian for an…

Chemical Physics · Physics 2018-04-18 Jinjun Liu

We investigate the occurrence of a phase transition, characterized by the spontaneous breaking of a discrete symmetry, in a driven-dissipative Bose-Hubbard lattice in presence of two-photon coherent driving. The driving term does not lift…

Quantum Physics · Physics 2017-09-20 Vincenzo Savona

We introduce a general approach for the simulation of quantum vibrational states of (symmetric and asymmetric) double-well potentials in molecules and materials for thermodynamic and spectroscopic applications. The method involves solving…

Through density functional theory and molecular dynamics calculations, we have analysed various metal polyhydrides to understand whether hydrogen is present in its molecular or atomic form - tetrahydrides of Ba,Sr,Ra, Cs and La;…

Materials Science · Physics 2023-04-27 Miriam Marqués , Miriam Pena Alvarez , Miguel Martinez-Canales , Graeme J Ackland

The temperature-induced orthorhombic to cubic phase transition in Li2C2 is a prototypical example of a solid to solid phase transformation between an ordered phase, which is well described within the phonon theory, and a dynamically…

Materials Science · Physics 2023-04-14 Johan Klarbring , Stanislav Filippov , Ulrich Häussermann , Sergei I. Simak

Quasi two-dimensional pattern forming systems with spontaneously broken isotropy represent a novel symmetry class, that is experimentally accessible in electroconvection of homeotropically aligned liquid crystals. We present a weakly…

patt-sol · Physics 2009-10-30 A. G. Rossberg , A. Hertrich , L. Kramer , W. Pesch

We investigated structural changes, phase diagram, and vibrational properties of hydrogen hydrate in filled-ice phase C2 by using first principles molecular dynamics simulation. It was found that the experimentally reported 'cubic'…

Materials Science · Physics 2012-09-13 Jingyun Zhang , Jer-Lai Kuo , Toshiaki Iitaka

We study the quantum phases of bosons with repulsive contact interactions on a two-leg ladder in the presence of a uniform Abelian gauge field. The model realizes many interesting states, including Meissner phases, vortex-fluids,…

Quantum Gases · Physics 2016-12-30 S. Greschner , M. Piraud , F. Heidrich-Meisner , I. P. McCulloch , U. Schollwöck , T. Vekua

A structural model of a one-component $\sigma$-phase crystal has been constructed by means of molecular dynamics simulation. The phonon dispersion curves and the vibrational density of states were computed for this model. The dependence of…

Condensed Matter · Physics 2009-10-31 S. I. Simdyankin , S. N. Taraskin , M. Dzugutov , S. R. Elliott