Intermolecular interaction energies of the alkane and benzene trimers derived from the isocyanurate molecules^a.

R	Sym.	Computational methodb
		B3LYP	B3LYP-GD3	B3LYP-GD3BJ	MP2
Primary alkyl-substituted isocyanurates
C 3 conformer
Me	C 3h	0.3	−0.5	−0.5	−0.4
Et	C 3v	0.3	−0.9	−0.9	−0.7
n-Pr	C 3	0.5	−1.9	−1.8	−1.6
n-Bu	C 3	0.6	−2.6	−2.5	−2.3
n-Hex	C 3	3.5	−9.5	−8.7	−7.3
n-Oct	C 3	5.1	−13.0	−12.0
C s conformer
Me	C s	0.3	−0.5	−0.5	−0.4
Et	C s	0.3	−0.9	−0.8	−0.7
n-Pr	C s	0.3	−1.0	−0.9	−0.8
n-Bu	C s	0.3	−1.0	−1.0	−0.9
n-Hex	C s	0.3	−1.0	−1.0	−0.9
n-Oct	C s	0.3	−1.1	−1.0
Secondary alkyl-substituted isocyanurates
i-Pr	C 3h	0.3	−1.3	−1.2	−1.1
i-Pr	C s	0.3	−1.3	−1.2	−1.1
Cy	C 3h	0.3	−1.5	−1.5	−1.4
Tri-t-butyl isocyanurate
t-Bu	C s	0.6	−2.3	−2.2	−1.9
t-Bu	C 3v	0.6	−2.2	−2.1	−1.9
Triphenyl isocyanurate
Ph	D 3	0.6	−1.0	−1.0	−1.0

^aThe intermolecular interaction energies were calculated with taking the corrections for the BSSEs into account. The calculated energy values are provided in kcal mol⁻¹.

^bThe basis set cc-pVTZ was employed.