Quantum chemical study of the interaction of nitrate anion with water

✍ Scribed by Christoph Ebner; Roland Sansone; Michael Probst

• Publisher: John Wiley and Sons
• Year: 1998
• Tongue: English
• Weight: 425 KB
• Volume: 70
• Category: Article
• ISSN: 0020-7608
• DOI: 10.1002/(sici)1097-461x(1998)70:4/5<877::aid-qua33>3.0.co;2-w

✦ Synopsis

The interaction between nitrate anion and water has been investigated Ž . by Hartree᎐Fock calculations with the 6-311 q G d, p basis set and by B3LYP density functional calculations with the aug-cc-pVTZ basis set. It is found that the global energy minimum is a planar configuration where both hydrogen atoms of water are coordinated to two oxygen atoms of NO y by distorted hydrogen bonds. In contrast to former studies 3 on NO y rH O this configuration is found to be asymmetric at the highest theoretical 3 2 level employed. The corresponding structure with C symmetry is a saddle point at 2 v slightly higher energy. A singly hydrogen-bonded configuration is still about 2.4 kcalrmol higher in energy. The shifts in the vibrational frequencies of water and nitrate upon complexation were calculated. A compact analytical potential function of NO y rH O for 3 2 use in statistical thermodynamic simulations was obtained from 390 points of the energy surface and an intramolecular force field for the nitrate anion is presented.