Prev. Article Next Article Table of Contents

Lab-Expt

Organometallic Computational Exercise: Semiempirical Molecular Orbital Calculations on (C6H6)Cr(CO)3 and (B3N3H6)Cr(CO)3

Your current credentials do not allow retrieval of the full text.

Purchase the full-text

PDF/HTML,
figures/images,
references and tables,
(where available)

James F. O'Brien

Department of Chemistry, Southwest Missouri State University, Springfield, MO 65804

Daniel T. Haworth

Department of Chemistry, Marquette University, Milwaukee, WI 53201

J. Chem. Educ., 2001, 78 (1), p 134

DOI: 10.1021/ed078p134

Publication Date (Web): January 1, 2001

Section:

History, Education, and Documentation

Abstract

A student exercise employing semiempirical molecular orbital calculations in the area of organometallic chemistry is presented. PM3 level calculations are applied to the ground-state structures of C₆H₆)Cr(CO)₃ and (B₃N₃H₆)Cr(CO)₃. The calculations are generally successful in computing the known features of the ground-state structures. Comparison of the geometries computed for free and complexed C₆H₆ and B₃N₃H₆ allow discussion of the reasons for the changes observed. The structures of the transition states for rotation of the rings with respect to Cr(CO)₃ are also computed. These results permit calculation of the activation energies for the ring rotations. The activation energies computed at the PM3 level are 0.4 and 18.3 kcal/mol for (C₆H₆)Cr(CO)₃ and (B₃N₃H₆)Cr(CO)₃, respectively. These results highlight the differences between the two molecules. Students are encouraged to comment on structural changes in the rings, on the phenomenon of ring rotation in these systems and others such as ferrocene, on the question of the aromaticity of the borazine ring, and on the effect of π back-bonding on the positions of the carbonyl stretching bands in the both complexes.

Keywords (Audience):

Upper-Division Undergraduate

Keywords (Domain):

Organic Chemistry

Keywords (Feature):

Molecular Modeling Exercises and Experiments

Keywords (Subject):

Computational Chemistry

View: Hi-Res PDF | PDF w/ Links

Citing Articles

View all 2 citing articles

Citation data is made available by participants in CrossRef's Cited-by Linking service. For a more comprehensive list of citations to this article, users are encouraged to perform a search in SciFinder.

This article has been cited by 2 ACS Journal articles (2 most recent appear below).

Using Molecular Modeling in Teaching Group Theory Analysis of the Infrared Spectra of Organometallic Compounds
Lihua Wang
Journal of Chemical Education2012 89 (3), 360-364
- Using Molecular Modeling in Teaching Group Theory Analysis of the Infrared Spectra of Organometallic Compounds
  Lihua Wang
  Journal of Chemical Education2012 89 (3), 360-364
  A new method is introduced for teaching group theory analysis of the infrared spectra of organometallic compounds using molecular modeling. The main focus of this method is to enhance student understanding of the symmetry properties of vibrational modes ...
  Abstract | Full Text HTML | Hi-Res PDF | PDF w/ Links
Structure and Bonding in Group 14 Congeners of Ethene: DFT Calculations in the Inorganic Chemistry Laboratory
Bennett R. Streit and David K. Geiger
Journal of Chemical Education2005 82 (1), 111
- Structure and Bonding in Group 14 Congeners of Ethene: DFT Calculations in the Inorganic Chemistry Laboratory
  Bennett R. Streit and David K. Geiger
  Journal of Chemical Education2005 82 (1), 111
  A computational chemistry experiment for an advanced inorganic chemistry laboratory is described. DFT calculations are performed to determine the optimized geometries of compounds of the type H2E=EH2. Structural parameters are compared for E=C, Si, and ...
  Abstract | Hi-Res PDF | PDF w/ Links