Structural parameters of concentrated aqueous solutions of LiCl over a wide temperature range

The structures of LiCl : 8.05H(2)O and LiCl : 3.15H(2)O solutions over a wi de temperature range and at a constant pressure (p = 20 MPa and T = 298-623 K) were studied by the method of integral equations. An analysis of the re sults obtained showed that the bulk water of the less concentrated solution lost its tetrahedral structure during heating. In the more concentrated so lution, the tetrahedral network of water is absent even at the standard tem perature. It was revealed that, irrespective of the concentration of the so lution, a temperature increase results in a considerable reduction in the c oordination ability of the ions. For the cation, the temperature effect is more pronounced. Upon heating, the concentration of hydrate-separated ion p airs in the systems under study considerably decreases. At the same time, i n the more concentrated solution, the fraction of contact ion pairs decreas es, whereas in the less concentrated solution, this quantity increases.