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The second-order nonlinear optical (NLO) properties of 5,10,15-triphenylcorrole (TPC), 5,10,15,20-tetraphenylporphyrin (TPP) and L-amino acid bridged bis-corroles 1, 2, 3 and 4 have been calculated by using TDHF/PM3 method based on the RHF/6-31G (TPC and TPP) or semiempirical PM3 (1, 2, 3, 4) optimized geometries. Calculation results showed TPC and TPP have C1 and D2h symmetry, respectively when N-H protons are localized on the nitrogen atoms. TPC is the second-order NLO active chromophore due to the cancellation of centrosymmetrical structure and its first hyperpolarizability β increases to 11.524×10-30 esu. Under electrical dipole approximation, β values of bis-corroles 1, 2, 3 and 4 vary from 9.831×10-30 to 14.221×10-30 esu, and no much improvement in the first hyperpolarizability was observed as compared to TPC monomer. However, β values of bis-corroles 1, 2, 3 and 4 are improved by about 4 times as compared to their bis-porphyrin counterparts. The analysis of β components indicates that β of this kind of bis-corroles is mainly contributed from its radial component βr. With the variation of amino acid side chains, βHRS, β, βxyz, βr and βa of bis-corroles change remarkably. Chiral L-amino acid bridged bis-corroles 2, 3 and 4 have a right-handed helix structure, and their chiral component βxyz matches βxyz ∝ r2ζ/L4 (helix parameters), showing the second-order chiral NLO response of these bis-corroles could be described by one-electron helical model theory. It was found that the radial component βr of chiral helix bis-corroles also matches β r ∝ r2ζ/L4.
The second-order nonlinear optical (NLO) properties of 5,10,15-triphenylcorrole (TPC), 5,10,15,20-tetraphenylporphyrin (TPP) and L-amino acid bridged bis-corroles 1, 2, 3 and 4 There have been calculated by using TDHF / PM3 method based on the RHF / 6-31G (TPC and TPP) or semiempirical PM3 (1, 2, 3, 4) optimized geometries. Calculation results showed TPC and TPP have C1 and D2h symmetry, respectively when NH protons are localized on the nitrogen atoms. TPC is the second-order NLO active chromophore due to the cancellation of centrosymmetric structure and its first hyperpolarizability β increases to 11.524 × 10-30 esu. Under electrical dipole approximation, β values of bis- corroles 1, 2, 3 and 4 vary from 9.831 × 10-30 to 14.221 × 10-30 esu, and no much improvement in the first hyperpolarizability was observed as compared to TPC monomer. However, β values of bis-corroles 1, 2 , 3 and 4 are improved by about 4 times as compared to their bis-porphyrin counterparts. The analysis of β components i ndicates that β of this kind of bis-corroles is mainly contributed from its radial component βr. With the variation of amino acid side chains, βHRS, β, βxyz, βr and βa of bis-corroles change remarkably. Chiral L-amino acid bridged bis-corroles 2, 3 and 4 have a right-handed helix structure, and their chiral component βxyz matches βxyz α r2ζ / L4 (helix parameters), showing the second-order chiral NLO response of these bis-corroles could be described by one -electron helical model theory. It was found that the radial component βr of chiral helix bis-corroles also matches β r α r2ζ / L4.