Theoretical Investigation on the Solubilization in Water of Functionalized Single-Wall Carbon Nanotubes

Table 1

Electronic properties for the C₆₀H₂₀ nanotube and the functionalized SWCNT formed in the reactions (3)–(6). The properties are HOMO-LUMO gap (H-L gap), magnitude of the dipole moment (𝜇_dip), and the Gibbs free energy of solvation (ΔG_solv).

System	Eb (eV)	H-L gap (eV)	𝜇dip (debye)	ΔGsolv (eV)
SWCNT	—	0.05	0.34	−0.73
CO2H-SWCNT (sidewall)	−2.00	0.38	3.60	−0.98
C6H3(CO2H)2-SWCNT (sidewall)	−2.73	0.41	3.96	−1.16
C6H4SO3H-SWCNT (sidewall)	−3.59	0.38	3.80	−1.12
CO2H-SWCNT radical (tip)	−3.88	0.41	9.79	−1.05