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Related Experiment Video

Updated: Jul 19, 2026

Reduction in Left Ventricular Wall Stress and Improvement in Function in Failing Hearts using Algisyl-LVR

Reduction in Left Ventricular Wall Stress and Improvement in Function in Failing Hearts using Algisyl-LVR

Published on: April 8, 2013

Invariom-model refinement of L-valinol.

Birger Dittrich¹, Parthapratim Munshi, Mark A Spackman

¹Chemistry M313, School of Biomedical, Biomolecular and Chemical Sciences, University of Western Australia, Crawley, WA 6009, Australia. birger@cyllene.uwa.edu.au

Acta Crystallographica. Section C, Crystal Structure Communications

|November 8, 2006

Summary

The crystal structure of L-valinol was determined using X-ray diffraction. Invariom refinement provided more accurate hydrogen bonding and geometry compared to traditional methods.

Related Experiment Videos

Last Updated: Jul 19, 2026

Reduction in Left Ventricular Wall Stress and Improvement in Function in Failing Hearts using Algisyl-LVR

Reduction in Left Ventricular Wall Stress and Improvement in Function in Failing Hearts using Algisyl-LVR

Published on: April 8, 2013

Area of Science:

Crystallography
Chemical Physics
Molecular Structure

Background:

L-valinol, a derivative of the amino acid L-valine, is important in chiral synthesis.
Accurate structural determination is crucial for understanding molecular interactions and reactivity.
X-ray diffraction is a primary technique for elucidating crystal structures.

Purpose of the Study:

To determine the precise crystal structure of L-valinol at low temperature (100 K).
To compare the accuracy of invariom structure refinement against the independent atom model.
To evaluate the hydrogen-bond pattern and geometric parameters obtained from different refinement methods.

Main Methods:

Single-crystal X-ray diffraction at 100 K.
Independent atom model refinement.
Invariom structure refinement.
Quantum chemical geometry optimization.

Main Results:

The crystal structure of L-valinol was successfully determined.
Invariom refinement yielded H-atom positions free from independent atom model bias.
The invariom refinement provided a more accurate hydrogen-bond pattern.
Geometry from invariom refinement showed improved agreement with quantum chemical calculations.

Conclusions:

Invariom refinement offers superior accuracy for hydrogen atom positions and hydrogen bonding in L-valinol.
This advanced refinement technique enhances the reliability of crystallographic data.
The findings support the use of invariom refinement for precise molecular structure analysis.