25,712 research outputs found

    Analytical Potential Energy Function for the Ground State X^{1} Sigma^+ of LaCl

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    The equilibrium geometry, harmonic frequency and dissociation energy of lanthanum monochloride have been calculated at B3LYP, MP2, QCISD(T) levels with energy-consistent relativistic effective core potentials. The possible electronic state and reasonable dissociation limit for the ground state are determined based on atomic and molecular reaction statics. Potential energy curve scans for the ground state X^{1} Sigma^+ have been carried out with B3LYP and QCISD(T) methods due to their better performance in bond energy calculations. We find the potential energy calculated with QCISD(T) method is about 0.5 eV larger than dissociation energy when the diatomic distance is as large as 0.8 nm. The problem that single-reference ab initio methods don't meet dissociation limit during calculations of lanthanide heavy-metal elements is analyzed. We propose the calculation scheme to derive analytical Murrell-Sorbie potential energy function and Dunham expansion at equilibrium position. Spectroscopic constants got by standard Dunham treatment are in good agreement with results of rotational analyses on spectroscopic experiments. The analytical function is of much realistic importance since it is possible to be applied to predict fine transitional structure and study reaction dynamic process.Comment: 10 pages, 1 figure, 3 table

    Kinematic Basis of Emergent Energetics of Complex Dynamics

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    Stochastic kinematic description of a complex dynamics is shown to dictate an energetic and thermodynamic structure. An energy function Ο†(x)\varphi(x) emerges as the limit of the generalized, nonequilibrium free energy of a Markovian dynamics with vanishing fluctuations. In terms of the βˆ‡Ο†\nabla\varphi and its orthogonal field Ξ³(x)βŠ₯βˆ‡Ο†\gamma(x)\perp\nabla\varphi, a general vector field b(x)b(x) can be decomposed into βˆ’D(x)βˆ‡Ο†+Ξ³-D(x)\nabla\varphi+\gamma, where βˆ‡β‹…(Ο‰(x)Ξ³(x))=\nabla\cdot\big(\omega(x)\gamma(x)\big)= βˆ’βˆ‡Ο‰D(x)βˆ‡Ο†-\nabla\omega D(x)\nabla\varphi. The matrix D(x)D(x) and scalar Ο‰(x)\omega(x), two additional characteristics to the b(x)b(x) alone, represent the local geometry and density of states intrinsic to the statistical motion in the state space at xx. Ο†(x)\varphi(x) and Ο‰(x)\omega(x) are interpreted as the emergent energy and degeneracy of the motion, with an energy balance equation dΟ†(x(t))/dt=Ξ³Dβˆ’1Ξ³βˆ’bDβˆ’1bd\varphi(x(t))/dt=\gamma D^{-1}\gamma-bD^{-1}b, reflecting the geometrical βˆ₯Dβˆ‡Ο†βˆ₯2+βˆ₯Ξ³βˆ₯2=βˆ₯bβˆ₯2\|D\nabla\varphi\|^2+\|\gamma\|^2=\|b\|^2. The partition function employed in statistical mechanics and J. W. Gibbs' method of ensemble change naturally arise; a fluctuation-dissipation theorem is established via the two leading-order asymptotics of entropy production as Ο΅β†’0\epsilon\to 0. The present theory provides a mathematical basis for P. W. Anderson's emergent behavior in the hierarchical structure of complexity science.Comment: 7 page

    Exotic phase separation in one-dimensional hard-core boson system with two- and three-body interactions

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    We investigate the ground state phase diagram of hard-core boson system with repulsive two-body and attractive three-body interactions in one-dimensional optic lattice. When these two interactions are comparable and increasing the hopping rate, physically intuitive analysis indicates that there exists an exotic phase separation regime between the solid phase with charge density wave order and superfluid phase. We identify these phases and phase transitions by numerically analyzing the density distribution, structure factor of density-density correlation function, three-body correlation function and von Neumann entropy estimator obtained by density matrix renormalization group method. These exotic phases and phase transitions are expected to be observed in the ultra-cold polar molecule experiments by properly tuning interaction parameters, which is constructive to understand the physics of ubiquitous insulating-superconducting phase transitions in condensed matter systems
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