Related Experiment Video
Updated: Jul 10, 2026

Achieving Moderate Pressures in Sealed Vessels Using Dry Ice As a Solid CO2 Source
Published on: August 17, 2018
Compressed hydrogen-bond effects in the pressure-frozen chloroacetic acid
Roman Gajda1, Andrzej Katrusiak
1Faculty of Chemistry, Adam Mickiewicz University, Grunwaldzka 6, 60-780 Poznań, Poland.
Abstract:
The competing effects of squeezed OH...O bonds, destabilizing the H-atom position, and of displaced hydrogen donor and acceptor groups, favouring the ordered H-atom sites, have been tuned by pressure in the pressure-frozen dichloroacetic acid. Its structure has been determined at 0.1, 0.7, 0.9 and 1.4 GPa: in this pressure range the crystals are stable in the monoclinic space group P2(1)/n. The molecules are O-H...O hydrogen bonded into dimers, which in turn interact via a unique pattern of halogen...halogen contacts. Between 0.1 and 1.4 GPa the OH...O bond is squeezed from 2.674 (13) to 2.632 (9) A. Within the pressure range investigated the hydrogen bonds are squeezed and the shear displacement of the molecules compensate, and the H atoms remain ordered.
Related Concept Videos
Hydrogen Bonds
Hydrogen Bonds
Comparing Intermolecular Forces: Melting Point, Boiling Point, and Miscibility
Temporary attractive forces like dispersion are present in all molecules, whether they are polar or nonpolar. They...
Intermolecular Forces
Intermolecular Forces
Molecular Shape and Polarity

