Abstract
Semiempirical and ab initio-based CI methods have been employed to study the low-lying electronic states of 2,4-pentadien-1-iminium cation and its N-substituted analogues with electron-donating (methyl, isopropyl) and electron-withdrawing (fluoromethyl) groups on nitrogen. Variations of the dihedral angles (Γ3, Γ4) of the ground state have given the global minima and global maxima at (180°, 180°) and (90°, 0°) conformations, respectively, with some exceptions in the case of fluoromethyl compound. Increase in the +I effect on nitrogen shifts the TICT conical intersection point away from the 90° (Γ3 dihedral angle) value, when the Γ4 value is kept fixed at 180°. Transition moment values of the allowed S0(1Ag –like) →S1 (2Bu–like) transitions are expectedly higher than the forbidden S0(1Ag –like) →S2(2Ag –like) transitions by almost 5.6 D. Radiative lifetime values of the first excited states are calculated to be around 215 ps for all the four compounds. At (180°, 180°) conformation the vertical excitation energy (VEE) between the S0 and S1 states of the 2,4-pentadieniminium cation is found to be 3.3 eV, which corresponds to the absorption wavelength value of roughly 375 nm. The VEE value increases with substituents having +I effect on nitrogen, while for the fluoromethyl compound it is calculated to be around 2.85 eV. The energy gap between the first two excited singlet states is found to have the least value in the isopropyl-substituted compound, where the S2 state contains a huge contribution from the HOMO2→LUMO2 configuration.
Similar content being viewed by others
References
Stoeckenius W and Rowen R 1962 J. Cell Biol. 34 65
Wald G 1968 Science 162 230
Fodor S P A, Ames J B, Gebhard R, van den Berg E M M, Stoeckenius W, Lugtenburg J and Mathies R A 1988 Biochemistry 27 7097
Schulten K and Tavan P 1978 Nature 272 85
Schulten K 1978 Energetics and structure of halophilic microorganism (eds) S R Caplan and M Ginzburg (Amsterdam: Elsevier) pp 331
Gerwert K and Siebert F 1986 J.EMBO 4 805
Sekharan S, Weingart O and Buss V 2006 Biophys. J.: Biophys. Lett. L07
Send R and Sundholm D 2008 J. Mol. Model 14 717
Gascón J A, Sproviero E M and Batista V S 2005 J. Chem. Theory Comput. 1 674
Gascón J A, Sproviero E M and Batista V S 2006 Acc. Chem. Res. 39 184
Smith S O, Myers A B, Pardoen J A, Winkel C, Mulder P P J, Lugtenburg J and Mathies R A 1984 Proc. Natl. Acad. Sci. USA 81 2055
Smith S O, Myers A B, Mathies R A, Pardoen J A, Winkel C, Van Den Berg E M M and Lugtenburg J 1985 Biophys. J. 47 653
Hudson B S and Birge R R 1999 J. Phys. Chem. A 103 2274
Buda F, Giannozzi P and Mauri F 2000 J. Phys. Chem. B 104 9048
Elia G R, Childs R F, Britten J F, Yang D S C and Santarsiero B D 1996 Can. J. Chem. 74 591401
Mathies R A, Cruz C H B, Pollard W T and Shank C V 1988 Science 240 777
Dobler J, Zinth W, Kaiser W and Oesterhelt D 1988 Chem. Phys. Lett. 144 215.
Zinth W and Oesterhelt D 1991 Photobiology (ed) E Ricklis (New York: Plenum Press) pp. 531
Arlt T, Schmidt S, Zinth W, Haupts U and Oesterhelt D 1995 Chem.Phys. Lett. 241 559
Xu D, Martin C and Schulten K 1996 Biophys. J. 70 453
Norton J E and Houk K N 2006 Mol. Phys. 104 993
Garavelli M 2006 Theor. Chem. Acc. 116 87
Cembran A, Bernardi F, Olivucci M and Garavelli M 2005 Proc. Natl. Acad. Sci. 102 6255
Ruiz D S, Cembran A, Garavelli M, Olivucci M and Fu W 2002 Photochem. Photobiol. 76 622
Dobado J A and Nonella M 1996 J. Phys. Chem. 100 18282
Conti I, Bernardi F, Orlandi G and Garavelli M 2006 Mol. Phys. 104 915
Conti I and Garavelli M 2007 J. Photochem. Photobiol. A: Chemistry 190 258
Ertl P 1990 Collect. Czech. Chem. Commun. 55 2874
Martin C H and Birge R R 1998 J. Phys. Chem. A 102 852
Tavernelli I, Röhrig U F and Rothlisberger U 2005 Mol. Phys. 103 963
Stewart J J P 1989 J. Comput. Chem. 10 209
Stewart J J P 1989 J. Comput. Chem. 10 221
Schmidt M W, Baldridge K K, Boatz J A, Elbert S T, Gordon M S, Jensen J J, Koseki S, Matsunaga N, Nguyen K A, Su S, Windus T L, Dupuis M and Montgomery J A 1993 J. Comput. Chem. 14 1347
Brooks B and Schaefer H F 1979 J. Chem. Phys. 70 5092
Brooks B, Laidig W, Saxe P, Handy N and Schaefer H F 1980 Phys. Scripta 21 312
Chattopadhyay A 2011 J. Phys. B: At. Mol. Opt. Phys. 44 165101
Chattopadhyay A 2010 J. Chem. Sci. 122 259
Davidson E R 1975 J. Comput. Phys. 17 87
Elbert S T 1987 Theoret. Chim. Acta 71 169
Weinhold F 1970 J. Chem. Phys. 54 1874
Bauschlicher C W and Langhoff S R 1991 Theoret. Chim. Acta 79 93
Koseki S and Gordon M S 1987 J. Mol. Spectrosc. 123 392
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
CHATTOPADHYAY, A. Comparative study of spectroscopic properties of the low-lying electronic states of 2,4-pentadien-1-iminium cation and its N-substituted analogues. J Chem Sci 124, 985–994 (2012). https://doi.org/10.1007/s12039-012-0311-8
Received:
Revised:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s12039-012-0311-8