Cation-water interactions. The M[sup +](H[sub 2]O)[sub n] clusters for alkali metals, M = Li, Na, K, Rb, and Cs

Journal Article · Thu Mar 09 00:00:00 EST 1995 · Journal of Physical Chemistry; (United States)

DOI:https://doi.org/10.1021/j100010a015· OSTI ID:6455422

Glendening, E D; Feller, D ^[1]

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1. Pacific Northwest Lab., Richland, WA (United States)

Gas-phase binding energies and enthalpies are reported for small M[sup +](H[sub 2]O)[sub n] clusters consisting of an alkali metal cation (Li[sup +], Na[sup +], K[sup +], Rb[sup +], or Cs[sup +]) with one to six water molecules. Ab initio molecular orbital calculations were performed at the RHF and MP2 levels of theory with split valence basis sets (3-21G, 6-31+G* with effective core potentials for the heavier alkali metals). Comparison with higher level calculations and with experimentally measured bond dissociation energies suggests that the RHF/6-31+G* method provides a reasonable description of cation-water interactions in the smallest (n = 1-3) clusters. Larger clusters, particularly those that involve water-water hydrogen-bonding interactions, require a correlated treatment at the MP2 level. This study serves to calibrate the RHF/6-31+G* and MP2/6-31+G* methods for applications to cation-ligand interactions in more extended systems (e.g., the ion-selective binding of crown ethers and cryptands) for which calculations at higher levels of theory are not currently feasible. 33 refs., 6 figs., 3 tabs.

• DOE Contract Number: AC06-76RL01830; FG06-89ER75522
• OSTI ID: 6455422
• Journal Information: Journal of Physical Chemistry; (United States), Vol. 99:10; ISSN 0022-3654
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
99 GENERAL AND MISCELLANEOUS//MATHEMATICS, COMPUTING, AND INFORMATION SCIENCE
CATIONS
HYDRATION
SOLVATION
ION PAIRS
BINDING ENERGY
ENTHALPY
ALKALI METALS
CESIUM IONS
EXPERIMENTAL DATA
INTERACTIONS
LITHIUM IONS
MOLECULAR ORBITAL METHOD
POTASSIUM IONS
RUBIDIUM IONS
SODIUM IONS
WATER
CALCULATION METHODS
CHARGED PARTICLES
DATA
ELEMENTS
ENERGY
HYDROGEN COMPOUNDS
INFORMATION
IONS
METALS
NUMERICAL DATA
OXYGEN COMPOUNDS
PHYSICAL PROPERTIES
THERMODYNAMIC PROPERTIES
400201* - Chemical & Physicochemical Properties
662300 - Specific Interactions
Decays & Processes- (1992-)
990200 - Mathematics & Computers