
















Chlorine














Calibration
of the







B1LYP/TZV(3df,2p)







model 













This
is the recommended model, calibration statistics for which are
shown below.














Calibration
was made by linear regression analysis of
calculated electric field gradients vs experimental nuclear quadrupole
coupling constants.
Calculations of the field gradients were made
on the equilibrium structures of the following molecules: 




















Figure
1. PDF
Calculated efg's
vs experimental nqcc's.














^{35}Cl
Calibration









Number
of
Points

66





Correlation
Coefficient

0.99996





Residual
Standard Deviation

0.49 MHz (1.1
%)





Slope, eQ_{eff}/h

19.166(21)
MHz/a.u.





Q_{eff} 
81.568(91) mb





Q

81.65(80) mb
[1]










Q_{eff}
differs from Q by 0.10
%. Using Q_{eff} for conversion of the
calculated efg's
to nqcc's yields for these 22 molecules a root mean square (RMS)
difference between calculated and experimental nqcc's of 0.481
MHz. Essentially the same RMS difference is obtained using Q,
namely 0.484 MHz. Therefore, for calculation of the chlorine
nqcc's (both isotopes), we use eQ/h rather than eQ_{eff}/h:
that is, for ^{35}Cl,
eQ/h = 19.185 MHz/a.u.,
and for ^{37}Cl,
15.120 MHz/a.u. 













^{37}Cl
Calibration 








Number
of
Points

51 *





Correlation
Coefficient

0.99996





Residual
Standard Deviation

0.44 MHz (1.1
%)





Slope, eQ_{eff}/h

15.106(20)
MHz/a.u.





Q_{eff} 
64.292(86) mb





Q

64.35(64) mb
[1]











*
No
experimental nqcc's for BCl, CH_{2}Cl_{2},
CH_{2}CCl_{2},
SiH_{2}Cl_{2},
and Cl_{2}O. 
















Reference







[1]
P.Pyykkö and
J.Li, 1992 Nuclear
Quadrupole Moments, Report HUKI 192, ISSN 07840365. 













"Nuclear
quadrupole coupling constants in alkali halide molecules: an ab
initio quantum chemical study" G.B.Bacskay and
A.D.Buckingham,
Mol.Phys. 91,391(1997). 













"Halogen
Nuclear Quadrupole Coupling Constants: Comparison of ab initio
Calculations which
include Correlation with Experiment" M.H.Palmer, J.A.BlairFish,
P.Sherwood, and M.F.Guest, Z.Naturforsch. 53a,383(1998).





















Table
of Contents







Chlorine Molecules

















