Hydrogen Cyanide Data

Hydrogen Cyanide Quantum Calculations

All of the displays on this page were created using our best optimized geometry calculations. The level of ab initio theory used was 6-311G. During the calculation, the geometry was approximated with a "balls on springs" model. Once the calculation was completed, the geometry with the lowest energy conformation was chosen as the optimum.

By clicking on the Bond Length button below, a live display of the optimized geometry for hydrogen cyanide will appear with the bond lengths in nanometers.

The experimental values for these bond lengths are 0.11560 nm between carbon and nitrogen and 0.10640 nm between carbon and hydrogen.³ These values give errors of 1.4% and 1.3% respectively.

The button below displays the single angle of hydrogen cyanide, which matches the experimental value of 180 degrees.

This button provides a live display of hydrogen cyanide's HOMO.

The HOMO are made entirely of the P_y orbitals of carbon and nitrogen, contributing to the triple bond between them.

Vibration 1.6 below has a frequency of 864.17 cm^-1. As can be seen from the animation, this vibration is caused mostly by a C-H bend.

Vibration 1.7 has a frequency of 864.23 cm^-1 and is also caused by a C-H bend.

Vibration 1.8 has a frequency of 2323.25 cm^-1 and is caused by stretching between the carbon, nitrogen, and hydrogen.

Vibration 1.9 has a frequency of 3630.54 cm^-1. This vibration is caused almost entirely by the C-H stretch.

These vibrations correspond to the observed peaks on the IR spectrum of hydrogen cyanide. To view a copy of this spectrum, see this NIST webpage.⁴

Upon comparison with the spectrum, the calculated vibrations appear to be too high. Vibration 1.9 has an experimental value of about 3325 cm^-1 and vibrations 1.7 and 1.6 are most likely in the 675 to 725 cm^-1 range. Vibration 1.8 may be the peak that is found near 1440cm^-1.⁴

Based on template by A. Herráez as modified by J. Gutow

Page skeleton and JavaScript generated by export to web function using Jmol 11.6.6 2008-09-20 22:06 on Mar 17, 2009.

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