Chemistry Reference
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Table 5
Calculated intermolecular distances
R
(Y-N) [A]oftheXY
···
NH
3
complexes as
obtained with different methods applying the aug-cc-pVTZ basis set
XY
MP2
CCSD(T) B3LYP
BH&HLYP Exp.
Refs.
F
2
R
(F-N)
2.61
2.63
2.10
2.73
[26]
R
CP
(F-N)
2.65
2.67
2.10
2.73
2.708
[7]
ClF
R
(Cl-N)
2.24
2.32
2.27
2.34
[26, 27]
R
CP
(Cl-N)
2.26
2.35
2.27
2.35
2.37
[8]
Cl
2
R
(Cl-N)
2.59
2.65
2.52
2.68
[26]
R
CP
(Cl-N)
±
2.63
2.72
2.52
2.69
2.73
0.03
[9]
BrF
R
(Br-N)
2.29
2.34
2.35
2.37
R
CP
(Br-N)
2.33
2.38
2.35
2.37
BrCl
R
(Br-N)
2.47
2.54
2.50
2.57
R
CP
(Br-N)
2.53
2.57
2.50
2.57
2.627
[10]
Br
2
R
(Br-N)
2.54
2.60
2.56
2.66
R
CP
(Br-N)
2.61
2.64
2.57
2.66
2.72
±
0.03
[11]
Calculated intramolecular distances
R
(X-Y) [A]oftheXY
Table 6
···
NH
3
complexes as
obtained with different methods applying the aug-cc-pVTZ basis set
XY
MP2
CCSD(T) B3LYP
BH&HLYP
Exp.
Refs.
F
2
R
CP
(F-F)
1.415
1.430
1.518
1.369
[26]
∆
R
CP
(F-F)
0.014
0.012
0.121
0.008
ClF
R
CP
(Cl-F)
1.712
1.702
1.733
1.668
[26, 27]
∆
R
CP
(Cl-F)
0.077
0.056
0.084
0.053
R
CP
(Cl-Cl)
Cl
2
2.034
2.044
2.088
2.023
2.00
[9, 26]
∆
R
CP
(Cl-Cl)
0.035
0.024
0.064
0.027
BrF
R
CP
(Br-F)
1.824
1.821
1.851
1.801
∆
R
CP
(Br-F)
0.066
0.056
0.076
0.059
BrCl
R
CP
(Br-Cl)
2.194
2.211
2.249
2.192
2.186
[10]
∆
R
CP
(Br-Cl)
0.056
0.051
0.079
0.051
Br
2
R
CP
(Br-Br)
2.324
2.341
2.385
2.327
2.335
[11]
∆
R
CP
(Br-Br)
0.045
0.038
0.068
0.041
in the complex. F
2
···
NH
3
is so far a special case as it constitutes an instance
of a very weak interaction, dominated by the dispersion contribution [25].
Therefore, in this case the deviation of the DFT methods from the CCSD(T)
resultsislarger.ThewideningoftheXYdistancesisactuallyslightlylarger
than in comparable (judged by the size of the interaction energy) hydrogen-
bonded complexes.
The calculated interaction energies are collected in Table 7. Experimen-
tal data on the stability of these complexes are not available. The CP-
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