SPECTROSCOPIC INVESTIGATION OF THE STRUCTURES OF THE CRYSTALLINE PHASES OF ACETYLENE.

Abstract

Infrared and Raman spectra of both crystalline phases of C2H2 and C2D2 were obtained. The Raman spectrum of liquid C2H2 was also observed. The spectra of the low temperature phase are interpreted as arising from an orthorhombic crystal with a D2h space group having two molecules per unit cell on C2h sites. The molecular axes are shown to be oriented perpendicular to the C2 axis at the site. The spectroscopic observations in the high temperature phase are in very close agreement with predictions based upon the x-ray determined Th(6) cubic space group with four molecules per unit cell on S6 sites. An approximate calculation of the lattice frequencies in this phase is in reasonable agreement with observation. Changes in intensities of some fundamentals with phase are qualitatively related to intermolecular hydrogen bonding. (Author)

Document Details

Document Type
Technical Report
Publication Date
Sep 01, 1968
Accession Number
AD0675272

Entities

People

  • George E. Leroi
  • William Hayden Smith

Organizations

  • Michigan State University

Tags

DTIC Thesaurus Topics

  • Acetylenes
  • Agreements
  • Alkynes
  • Cooperation
  • Frequency
  • High Temperature
  • Hydrogen
  • Intensity
  • Low Temperature
  • Molecules
  • Observation
  • Raman Spectra
  • Spectra
  • X Rays

Fields of Study

  • Chemistry
  • Materials science

Readers

  • Materials Science and Engineering.
  • Spectroscopy.

Technology Areas

  • Space