L. Dalton, P. Sullivan, and D. Bale, Electric Field Poled Organic Electro-optic Materials: State of the Art and Future Prospects, Chemical Reviews, vol.110, issue.1, pp.25-55, 2010.
DOI : 10.1021/cr9000429

S. Marder and G. Ed, Themed issue on organic nonlinear optics, J Mater Chem Lenze MR; Kronenberg NM; Krause AM, vol.19, pp.7381-7568, 2009.

K. Meerholz and F. Würthner, NIR-absorbed merocyanin dyes for BHJ solar cells, Chem Mater, vol.26, pp.4856-4866, 2014.

. Skindhoej, Large first hyperpolarizability in push-pull polyenes by tuning of the bond length alternation and aromaticity (b) Blanchard-Desce M; Alain V; Bedworth PV; Marder SR; Fort A; Runser C, Science Barzoukas M; Lebus, vol.263, pp.511-514, 1994.

R. Wortmann, Large quadratic hyperpolarizabilities with donar-acceptor polyenes exhibiting optimum bond length alternation: correlation between structure and hyperpolarizability, Chem Eur J, vol.3, pp.1091-1104, 1997.

M. Blanchard-desce, U. Gubler, C. Bosshard, V. Günter, J. Muller et al., Molecular engineering of push-pull phenyl polyenes for nonlinear optics: improved solubility, stability, and nonlinearities (d) Plaquet A; Champagne B, Adv Mater Kulhánek J; Bures F, vol.11, pp.1210-1214, 1999.

V. Rodriguez, Effects of the nature and length of the ?-conjugated bridge on the second-order nonlinear optical responses of push-pull molecules including 4,5- dicyanoimidazole and their protonated forms, Chem Phys Chem, vol.12, issue.3245, 2011.

B. Villacampa and B. Allain, 4H-Pyran-4-ylidenes: strong proaromatic donors for organic nonlinear optical chromophores, J Org Chem, vol.74, pp.6647-6657, 2009.

J. Orduna, R. Alicante, and B. Villacampa, Linear and V-shaped nonlinear optical chromophores with multiple 4H-pyran-4-ylidene moieties, J Org Chem, vol.75, 2010.

1. Davies, J. Elangovan, A. Sullivan, P. Olbricht, B. Bale et al., -aryl-amino Donor-Based Chromophores: Design, Synthesis, and Electrooptic Activity, 10565?10575. (e) Alías S; Andreu R; Cerdán MA, 2008.
DOI : 10.1021/ja8007424
URL : https://hal.archives-ouvertes.fr/hal-00309864

J. Orduna, P. Romero, B. Villacampa, S. Jang, J. Luo et al., Synthesis, characterization and optical properties of merocyanines derived from malononitrile dimer, Tetrahedron Lett, vol.48, pp.6539-6542, 2007.

C. Spangler and V. Mccoy, Preparation of Conjugated Aromatic Polyenals by Wittig Oxopropenylation, Synthetic Communications, vol.76, issue.1, pp.51-59, 1998.
DOI : 10.1039/jr9610002130

R. Andreu, L. Carrasquer, M. Cerdán, A. Fernández, S. Franco et al., A simple synthesis of 2-methyl-1,3-dithiolium and related cations, Synlett, pp.1470-1472, 2007.

A. Fatiadi, New applications of malononitrile in organic chemistry (d) Freeman F. The chemistry of malononitrile (d) Bardasov IN; Mihailov DL; Alekseeva AU, Synthesis Chemical Rev, vol.69, pp.165-204, 1969.

M. Blanchard-desce, Combination of cyanine behavior and giant hyperpolarizability in novel merocyanine dyes: beyond the bond length alternation (BLA) paradigm, Chem Eur J, vol.21, 2015.

M. Khan, J. Fleury, P. Baumlin, and C. Hubschwerlen, A new route to trinuclear carbocyanines, Tetrahedron, vol.41, issue.22, pp.5341-5345, 1985.
DOI : 10.1016/S0040-4020(01)96787-0

J. Oudar and V. Chemla, Hyperpolarizabilities of the nitroanilines and their relations to the excited state dipole moment, The Journal of Chemical Physics, vol.66, issue.6, pp.2664-2668, 1977.
DOI : 10.1063/1.434213

T. Bahers and . Le, Adamo C; Ciofini I. What is the ''best'' atomic charge model to describe through-space charge-transfer excitations?, Phys Chem Chem Phys, vol.14, pp.5383-5388, 2012.

S. Brasselet and J. J. Zyss, Multipolar molecules and multipolar fields: probing and controlling the tensurial nature of nonlinear media (b) Castet F; Bogdan E; Plaquet L; Ducasse B; Champagne V; Rodriguez V. Reference molecules for nonlinear optics: A joint experimental and theoretical investigation, J Opt Soc Am B, vol.15, issue.25, 1998.

S. Benight, D. Bale, B. Olbricht, and L. Dalton, Organic electro-optics: Understanding material structure/function relationships and device fabrication issues, Journal of Materials Chemistry, vol.20, issue.40, pp.7466-7475, 2009.
DOI : 10.1039/b905368a

H. Anderson, Thiophene-based dyes for probing membranes, Org Biomol Chem, vol.13, pp.3792-3802, 2015.

P. Venkatakrishnan, R. Pandey, F. Terenziani, P. Das, and M. Blanchard-desce, Combined transparency and optical nonlinearity enhancement in flexible covalent multimers by operating through-space interactions between dipolar chromophores, Phys Chem Chem Phys, vol.16, pp.9096-9103, 2014.

R. Bersohn, Y. Pao, and H. Frisch, Double???Quantum Light Scattering by Molecules, The Journal of Chemical Physics, vol.45, issue.9, p.3184, 1966.
DOI : 10.1063/1.1728092

J. Tomasi and M. Persico, Molecular Interactions in Solution: An Overview of Methods Based on Continuous Distributions of the Solvent, Chemical Reviews, vol.94, issue.7, p.2027, 1994.
DOI : 10.1021/cr00031a013

J. Tomasi, B. Mennucci, and R. Cammi, Quantum mechanical continuum solvation models