Pure rotational spectrum and model calculations of indole–water

Abstract

The molecular beam Fourier transform microwave spectra of two isotopomers of the 1:1 complex between indole and water have been measured. The water molecule has been reliably located in the complex from these experimental data. The complex has a Cs symmetry with an N–H⋯O hydrogen bond and the plane of the H2O molecule perpendicular to the indole plane. The two-dimensional potential energy surface of the internal rotation and inversion of water in the complex, evaluated with B3LYP/6-31G** or MP2/6-31G** quantum chemical calculations, suggests the tunneling motion of water to take place with the contribute of both motions. The experimental evidence combined with flexible model calculations, indicate, however, that the tunneling motion is mainly an internal rotation of water around its C2 symmetry axis.

Hydrogen‐Bond Cooperativity in Formamide2–Water: A Model for Water‐Mediated Interactions

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Microwave Spectroscopy of Biomolecular Building Blocks

“…For that reason, complete series of molecules of biological interest, such as building blocks, have escaped microwave spectroscopy studies. Several laboratories have incorporated heatable nozzles [40][41][42] into their microwave spectrometers to overcome the problem, but, in many cases, thermal instability constituted an important drawback. The pioneering works of Brown [43] or Suenram [44] and co-workers on molecular building blocks were carried out using such heating methods.…”

Interactions Between Organic Molecules and Water: Rotational Spectrum of the 1:1 Oxetane–Water complex

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