. Author manuscript; available in PMC: 2011 Mar 17.

Published in final edited form as: J Am Chem Soc. 2010 Mar 17;132(10):3304–3311. doi: 10.1021/ja903653j

Table 1.

Interaction energies (kcal mol⁻¹) for C₆H₆^…C₆H₅R benzene sandwich dimers, relative to the unsubstituted benzene dimer.^a Positive numbers indicate enhanced interaction relative to the unsubstituted dimer.

	Me	OH	OMe	F	Cl	Br	CN
M05-2X	0.3	0.4	0.3	0.5	0.8	1.0^b	1.3
M06-2X	0.4	0.5	0.6	0.6	1.0	1.1^b	1.4
CCSD(T)^c	0.5^d	0.4^d	0.6^e	0.5^d	0.9^e	1.1^e	1.3^d

The interaction energy for the unsubstituted benzene dimer is −0.5 and −1.0 kcal mol⁻¹ at the M05-2X/6-31+G(d) and M06-2X/6-31+G(d) level of theory, respectively. The M05-2X/AVDZ′ and M06-2X/AVDZ′ values are −0.7 and −1.6, respectively. The CCSD(T) value from ref 9 is −1.8 kcal mol⁻¹.

AVDZ′ basis set.

Estimated CCSD(T)/aug-cc-pVTZ

From ref 9.

This work.