Ion-Stockmayer clusters: Minima, classical thermodynamics, and variational ground state estimates of Li{sup +}(CH{sub 3}NO{sub 2}){sub n} (n = 1–20)

Journal Article · Mon Dec 07 00:00:00 EST 2015 · Journal of Chemical Physics

DOI:https://doi.org/10.1063/1.4936587· OSTI ID:22493293

Curotto, E., E-mail: [e-mail] ^[1]

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1. Department of Chemistry and Physics, Arcadia University, Glenside, Pennsylvania 19038-3295 (United States)

Structural optimizations, classical NVT ensemble, and variational Monte Carlo simulations of ion Stockmayer clusters parameterized to approximate the Li{sup +}(CH{sub 3}NO{sub 2}){sub n} (n = 1–20) systems are performed. The Metropolis algorithm enhanced by the parallel tempering strategy is used to measure internal energies and heat capacities, and a parallel version of the genetic algorithm is employed to obtain the most important minima. The first solvation sheath is octahedral and this feature remains the dominant theme in the structure of clusters with n ≥ 6. The first “magic number” is identified using the adiabatic solvent dissociation energy, and it marks the completion of the second solvation layer for the lithium ion-nitromethane clusters. It corresponds to the n = 18 system, a solvated ion with the first sheath having octahedral symmetry, weakly bound to an eight-membered and a four-membered ring crowning a vertex of the octahedron. Variational Monte Carlo estimates of the adiabatic solvent dissociation energy reveal that quantum effects further enhance the stability of the n = 18 system relative to its neighbors.

• OSTI ID: 22493293
• Journal Information: Journal of Chemical Physics, Vol. 143, Issue 21; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); ISSN 0021-9606
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
ALGORITHMS
AMMONIUM NITRATES
COMPUTERIZED SIMULATION
DISSOCIATION ENERGY
GROUND STATES
LAYERS
LITHIUM COMPOUNDS
LITHIUM IONS
MONTE CARLO METHOD
NITROMETHANE
OPTIMIZATION
SOLVATION
SOLVENTS
SPECIFIC HEAT
STABILITY
TEMPERING
THERMODYNAMICS
VARIATIONAL METHODS