Skip to main content
U.S. flag

An official website of the United States government

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Wavenumbers for Calibration of IR Spectrometers

NIST Standard Reference Database 118

Last Update to Data Content: April 1998 | Version History |  Disclaimer | DOI:
Arthur G. Maki and Joseph S. Wells


This computer based version of NIST Special Publication 821 contains the bibliography and atlas as updated through November 1994. The calibration lines in this atlas, indicated by an asterisk (*), are based on frequency rather than wavelength measurements. Since a limited number of absolute frequency measurements have been made, additional data from measurements using other techniques are used to determine frequency differences within each band. Data from these complementary techniques include the best Fourier transform measurements available. The bibliography lists papers that give relevant spectroscopic measurements for the five molecules used in the atlas, CO, OCS, N2O, NO, and CS2.

The atlas and wavenumber tables consist of many pages of spectral maps accompanied by tables of transition wavenumbers and their identity. The tables are calculated from molecular constants derived for this work and based on frequency measurements. The primary calibration molecules are the linear triatomics, carbonyl sulfide (OCS) and nitrous oxide (N2O), which cover portions of the infrared spectrum ranging from 488 to 3120 cm-1. Some gaps in the coverage afforded by OCS and N2O are partially covered by NO, CO, and CS2. An additional region from 4000 to 4400 cm-1 based on CO is also included.


NIST Standard Reference Database 118 | Online: May 1995 | Last Update: April 1998 | Customer Support


Sensor Science Division Chief

Created July 23, 2009, Updated December 6, 2019