Calculated electric quadrupole moments
The electric quadrupole moment is a measure of the charge distribution in a molecule.
The calculated quadrupole moments are reported as symmetric matrix
components in units of D Å (Debye times Angstrom) or e a02 (electron charge times bohr squared).
The currently chosen quadrupole units are D Å
To change units see section: FAQ Help; Units; Choose Units; Dipole and Quadrupole
Please enter the chemical formula
Rules for chemical formula
- Enter a sequence of element symbols followed by numbers
to specify the amounts of desired elements (e.g., C6H6).
- Elements may be in any order.
- If only one of a given atom is desired, you may omit
the number after the element symbol.
- Parentheses may be used to group atoms.
- Multiple specifications for an atom will be added.
This means that CH3(CH2)4CH3 will be
treated the same as C6H14.
- A comma delimited list of several species may be entered.
- Ions are indicated by placing + or - at the end of the formula (CH3+, BF4-, CO3--)
Species in the CCCBDB
- Mostly atoms with atomic number less than than 36 (Krypton), except for most of the transition metals.
See section I.B.1 for a periodic table view.
- Six or fewer heavy atoms and twenty or fewer total atoms.
Versions 8 and higher have a few substituted benzenes with more than six heavy atoms.
Versions 12 and higher have bromine-containing molecules.
References dealing with electric quadrupoles
|RH Orcutt "Influence of Molecular Quadrupole Moments on the Second Virial Coefficient" J. Chem. Phys. 39(3), 605, 1963
|Hellwege, KH and AM Hellwege (eds.). Landolt-Bornstein: Group II: Volume 6 Molecular Constants from Microwave, Molecular Beam, and Electron Spin Resonance Spectroscopy Springer-Verlag. Berlin. 1974.
|C Graham, DA Imrie, RE Raab "Measurement of the electric quadrupole moments of CO2, CO, N2, Cl2 and BF3" Mol. Phys. 93(1), 1998, 49-56
|S Hofginger, M Wendland "Method/Basis Set Dependence of the Traceless Quadrupole Moment Calculation for N2, CO2, SO2, HCl, CO, NH3, PH3, HF, and H2O" Int. J. Quantum Chem. 86, 199-217, (2002)
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