Crystal and molecular structure, hydrogen bonding and electrostatic interactions of bis(trigonelline) hydrogen perchlorate monohydrate

Abstract

Bis(trigonelline) hydrogen perchlorate monohydrate, (TRG) 2H·ClO 4·H 2O, crystallizes in space group P2 1. A pair of TRG molecules is bridged by an asymmetrical O·H·O hydrogen bond of length 2.484(3) Å to form a homoconjugated cation. Water molecules and ClO 4 anions are linked alternatively by hydrogen bonds of lengths 2.961(3) and 3.254(3) Å into planar, zigzag chains along the [z] direction. Both the ClO 4 anion and H 2O molecule display additionally electrostatic interactions with two positively charged nitrogen atoms of neighboring TRG molecules. The isolated entities of the complex were analyzed at the B3LYP/6-31G(d,p) level of theory in order to determine the influence of the ClO 4 anion and H 2O molecule on the hydrogen bond in (TRG·H·TRG). The FTIR spectrum shows a broad and intense absorption in the 1500–400 cm −1 region, typical for short hydrogen bonds. Two bands at 3675 and 3580 cm −1 confirmed a weak hydrogen bonds between water molecules and ClO 4 anions.