Density Functional Theory Study of Red-shifted Hydrogen Bonds of 4-Pyridinemethanol with Water

✍ Scribed by Quan LI; Jing CAI; Jun-Rong CHEN; Ke-Qing ZHAO

• Publisher: John Wiley and Sons
• Year: 2008
• Tongue: English
• Weight: 144 KB
• Volume: 26
• Category: Article
• ISSN: 0256-7660
• DOI: 10.1002/cjoc.200890050

✦ Synopsis

Abstract

The hydrogen bonds of 1:1 and 1:2 complexes formed between 4‐pyridinemethanol and water have been investigated using a density functional theory (DFT) method and 6‐311++G∗︁ ∗︁ basis set, and three and eight stable geometries have been obtained for 1:1 and 1:2 complexes, respectively. The interaction energy is −20.536 and −44.256 kJ/mol for the most stable 1:1 and 1:2 complexes, respectively, after the basis set superposition error and zero‐point corrections. The formation of OH···N(O) hydrogen bonds makes OH symmetric stretching modes in the complexes red‐shifted relative to those of the monomer. The natural bond orbit analysis indicates that the intermolecular charge transfer between 4‐pyridinemethanol and water is 0.02642 e and 0.03813 e for the most stable 1:1 and 1:2 complexes, respectively. In addition, TD‐B3LYP/6‐311++G∗︁ ∗︁ calculations show that formation of water‐OH···N and water‐OH···OH hydrogen bonds makes maximum absorbance wavelength λ~max~ blue‐shifted 8–16 nm and red‐shifted 4–11 nm compared to that of 4‐pyridinemethanol monomer molecule, respectively.