VSEPR

Science & Engineering abbreviation · Chemistry

VSEPR
Stands forValence shell electron pair repulsion
CategoriesScience & Engineering

VSEPR stands for Valence shell electron pair repulsion, a chemistry abbreviation.

Model that predicts molecular shapes from the idea that electron pairs around a central atom repel one another and spread as far apart as possible. It explains why methane is tetrahedral, ammonia trigonal pyramidal and water bent, and is a staple of high school and introductory college chemistry.

Example: Use VSEPR theory to predict the shape of sulfur hexafluoride.

Usage notes

Commonly pronounced "vesper." Ronald Gillespie and Ronald Nyholm developed the model in 1957, building on earlier work by Nevil Sidgwick and Herbert Powell. Lone pairs repel more strongly than bonding pairs, which squeezes the H-O-H angle in water to about 104.5 degrees. AXE notation summarizes each case, such as AX2E2 for water.

More chemistry abbreviations

  • AAS – Atomic absorption spectroscopy
  • ABS – Acrylonitrile butadiene styrene
  • Ac – Acetyl group
  • aq – Aqueous
  • BPA – Bisphenol A
  • CAS – Chemical Abstracts Service
  • CFC – Chlorofluorocarbon
  • CH4 – Methane
  • CO – Carbon monoxide
  • CO2 – Carbon dioxide
  • conc. – Concentrated
  • DCM – Dichloromethane

See all 106 chemistry abbreviations →

Edited by the AbbreviationList.com team. Spotted an error or a missing meaning? Contact us.