The Electronic Structure of Short Carbon Nanotubes: The Effects of Correlation

Table 4

CAS-CI and the NEVPT2 energies in kJ mol⁻¹ for the class of nanotubes , with odd and even. All possible states for a CAS of four electrons in four orbitals have been calculated.

n∖p	State	2		4		6
		CAS-CI	NEVPT2	CAS-CI	NEVPT2	CAS-CI	NEVPT2
7		−23.1	−56.5	−0.9	−9.7	−4	−2.3
		−14.8	−37.8	−0.6	−6.5	−2	−1.6
		0.0	0.0	0.0	0.0	0.0	0.0
		346.4	−49.2	396.9	−4.5	398.7	−1.7
		178.0	−17.1	198.5	0.6	199.3	2.7
		203.1	−7.7	199.4	1.3	199.4	2.7
		406.0	−7.4	398.8	1.7	398.8	2.4
		446.6	27.7	569.3	45.9	599.7	97.2
9		−13.3	−51.5	−0.5	−15.9	−2	−7.5
		−8.6	−34.8	−0.3	−10.6	−1	−5.0
		0.0	0.0	0.0	0.0	0.0	0.00
		333.7	−47.4	387.8	−37.9	382.4	−34.2
		384.5	−33.5	380.1	−29.3	382.5	−32.4
		192.3	−21.9	190.0	−15.3	191.2	−15.5
		176.5	−18.0	189.5	−15.5	191.2	−15.5
		409.9	52.2	504.0	41.5	547.8	−37.7
11		−10.1	−61.6	−0.4	−35.8	−3	−27.8
		−6.6	−41.6	−0.3	−23.9	−2	−18.5
		0.0	0.0	0.0	0.0	0.0	0.0
		309.1	−52.3	360.8	−88.9	362.9	−87.6
		181.4	−38.6	181.1	−39.4	181.5	−43.6
		168.6	−26.3	180.7	−39.2	181.4	−43.7
		370.5	51.3	449.8	2.8	485.8	−55.9
		360.3	51.4	362.3	−70.8	362.9	−82.1