**************** The 8th., Lab Seminar *****************

Date: Tue, July 25, 2006  PM 1:30-

Place: No.616 Seminar room
　　　　　　 Graduate School of Information Science

Speaker: Yukinori Nakagawa

Title: Ionization of Bases in Water:Structure and Stability of the NH4+…OH-Ionic Forms in Ammonia-Water Clusters

Abstruct:
 The structure and stability of the NH4+OH-ionic forms resultant from the equilibrium NH3+H2O<->NH4++OH-is 
analyzed by Hartree-Fock,second-order Moller-Plesset,and the  Becke-Lee-Yang-Parr density functional.
Our results show that a double ionic cluster NH4+…(H2O)…OH-,in which three molecules are located between the NH4
+and OH-ions, is stable and lies 5-10kcal/mol higher than various neutral clusters containing one ammonia and four 
water molecules. The process of formation of the double ionic cluster from a geometrically similar neutral cluster is 
shown to be synchronic, with the two protons being simultaneously transferred. The MP2 and BLYP methods give a similar 
description of the structure and stability of these clusters.

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