A comparison of the structures of pyrazole, 3,5-dimethylpyrazole and 3,5-bis(trifluoromethyl)pyrazole

theoretical calculations (STO-3G), microwave, electron diffraction and crystallography

I. Hargittai, Jon Brunvoll, Concepcion Foces-Foces, Antonio L. Llamas-Saiz, J. Elguero

Research output: Contribution to journalArticle

21 Citations (Scopus)

Abstract

The first two examples of pyrazole structures determined by electron diffraction are reported. These geometries and that of pyrazole itself (known from a microwave study) are discussed in comparison with STO-3G ab initio calculations and with X-ray geometries. Theoretically optimized geometries agree with the experimental ones, both describing consistently the electronic effects and conformation of methyl and trifluoromethyl substituents with regard to the solid state geometries, it appears that 3,5-dimethylpyrazole has a classical Cs structure in the gas phase consistent with the averaged C2v structure of the crystal (dynamically disordered).

Original languageEnglish
Pages (from-to)211-217
Number of pages7
JournalJournal of Molecular Structure
Volume291
Issue number2-3
DOIs
Publication statusPublished - Feb 28 1993

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Crystallography
Microwaves
Electron diffraction
crystallography
electron diffraction
Electrons
microwaves
Geometry
geometry
Gases
X-Rays
Conformations
vapor phases
solid state
X rays
Crystals
pyrazole
3,5-dimethylpyrazole
electronics
crystals

ASJC Scopus subject areas

  • Structural Biology
  • Organic Chemistry
  • Physical and Theoretical Chemistry
  • Spectroscopy
  • Materials Science (miscellaneous)
  • Atomic and Molecular Physics, and Optics

Cite this

A comparison of the structures of pyrazole, 3,5-dimethylpyrazole and 3,5-bis(trifluoromethyl)pyrazole : theoretical calculations (STO-3G), microwave, electron diffraction and crystallography. / Hargittai, I.; Brunvoll, Jon; Foces-Foces, Concepcion; Llamas-Saiz, Antonio L.; Elguero, J.

In: Journal of Molecular Structure, Vol. 291, No. 2-3, 28.02.1993, p. 211-217.

Research output: Contribution to journalArticle

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