Czarnacki, Maciej and Halas, Stanislaw (2011) Reduced partition function ratios for isotopes of hydrated alkali and alkaline earth ions calculated by a simple electrostatic model. Central European Geology, 54 (12). pp. 189198. ISSN 17882281

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Abstract
Abstract We describe a simple electrostatic model of hydrated ions [M(H2O)n]+ (n = 3–18, M = Li, Mg, Ca, K) which enables to calculate ion vibration frequency of the ground state. In this model the considered ion with a reduced mass vibrates in quasispherical well formed by the iondipole attractive potential and repulsive valence potential, these simplifications allowed to solve one dimensional Schrödinger equation, whilst the calculated ground state was considered as one of triply degenerated state of the three dimensional motion of the ion vs. hydration shell. The reduced partition function ratios were calculated from the vibration frequencies using Urey's (1947) harmonic approximation formula. The results obtained in this way are in good agreement with those obtained by much more laborious ab initio molecular orbital methods, like SCF HartreeFock, DFT, MP2, etc. Moreover, we were able to extend calculations to hydrated Li and K ions surrounded with two shells of water molecules. These results are the first estimations of the upper limit of isotope fractionation in water solutions, which are 99.3‰ for Li and only 2.5‰ for K isotopes.
Item Type:  Article 

Subjects:  Q Science / természettudomány > QE Geology / földtudományok 
Depositing User:  xBarbara xBodnár 
Date Deposited:  20 Jun 2017 13:25 
Last Modified:  04 Apr 2023 12:55 
URI:  http://real.mtak.hu/id/eprint/55076 
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