National Institute of Standards and Technology
Computational Chemistry Comparison and Benchmark DataBase
Release 17bSeptember 2015
NIST Standard Reference Database 101
IIExperimental data
IIICalculated data
IVData comparisons
VCost comparisons
VIInput and output files
VIITutorials and Units
VIIILinks to other sites
XOlder CCCBDB versions
XIII Vibrations
XIVReaction data
XVEntropy data
XVIBibliographic data
XVIIIon data
XVIIIBad calculations
XIXIndex of properties
XXH-bond dimers

NIST policy on privacy, security, and accessibility.

Please rate our products
© 2013 copyright by the U.S. Secretary of Commerce on behalf of the United States of America. All rights reserved.

The National Institute of Standards and Technology (NIST) is an agency of the U.S. Department of Commerce.

Please send questions, comments, corrections, additions and suggestions to

return to home page

II.A.1. (XV.A.)

Listing of experimental data for SeO (Selenium monoxide)

State Conformation
3Σ C*V
Enthalpy of formation (Hfg), Entropy, Integrated heat capacity (0 K to 298.15 K) (HH), Heat Capacity (Cp)
Property Value Uncertainty units Reference Comment
Hfg(298.15K) enthalpy of formation 57.40 6.21 kJ mol-1 2005Se
Hfg(0K) enthalpy of formation   6.21 kJ mol-1 2005Se
Entropy (298.15K) entropy 233.70 1.00 J K-1 mol-1 2005Se
Heat Capacity (298.15K) heat capacity 32.52 0.25 J K-1 mol-1 2005Se
Information can also be found for this species in the NIST Chemistry Webbook
Vibrational levels (cm-1) vibrations
Mode Number Symmetry Frequency (cm-1) Frequency Reference Intensity (km mol-1) Int. unc. Intensity Reference Comment
1 Σ 915 webbook       omega e

vibrational zero-point energy: 457.3 cm-1
Calculated vibrational frequencies for SeO (Selenium monoxide).
Rotational Constants (cm-1) rotational constants
See section I.F.4 to change rotational constant units
A B C reference comment
  0.47058 0.47058 NISTdiatomic

Calculated rotational constants for SeO (Selenium monoxide).

Product of moments of inertia moments of inertia
35.82285amu Å2   5.948616E-39gm cm2
Geometric Data
picture of Selenium monoxide

Point Group C∞v

Internal coordinates
distances (r) in Å, angles (a) in degrees, dihedrals (d) in degrees

Description Value unc. Connectivity Reference Comment
Atom 1 Atom 2 Atom 3 Atom 4
rSeO 1.639 0.001 1 2 NISTdiatomic re


Atom x (Å) y (Å) z (Å)
Se1 0.0000 0.0000 0.0000
O2 0.0000 0.0000 1.6395

Atom - Atom Distances bond lengths
Distances in Å

  Se1 O2
Se1   1.6395
O2 1.6395  

Calculated geometries for SeO (Selenium monoxide).

Bond descriptions

Examples: C-C single bond, C=C, double bond, C#C triple bond, C:C aromatic bond
Bond Type Count
O-Se 1


Atom 1 Atom 2
Se1 O2
Electronic energy levels (cm-1)
Energy (cm-1) Degeneracy reference description
0 0 webbook 3Σ
165.9 2 webbook 1?
5300 2 webbook
9723.5 1 webbook

Electron Affinity (eV)

Electron Affinity unc. reference
1.456 0.020 webbook
Dipole, Quadrupole and Polarizability
Electric dipole moment dipole
Calculated electric dipole moments for SeO (Selenium monoxide).
Electric quadrupole moment quadrupole
Calculated electric quadrupole moments for SeO (Selenium monoxide).

By selecting the following links, you may be leaving NIST webspace. We have provided these links to other web sites because they may have information that would be of interest to you. No inferences should be drawn on account of other sites being referenced, or not, from this page. There may be other web sites that are more appropriate for your purpose. NIST does not necessarily endorse the views expressed, or concur with the facts presented on these sites. Further, NIST does not endorse any commercial products that may be mentioned on these sites. Please address comments about this page to
squib reference DOI
2005Se A Olin, B Nolang, G Osadchii, L-O Ohman, E Rosen, "CHEMICAL THERMODYNAMICS OF SELENIUM", OECD Nuclear Energy Agency, Elsevier, 2005  
NISTdiatomic NIST Diatomic Spectral Database (  
webbook NIST Chemistry Webbook (  

Got a better number? Please email us at