We found a match
Your institution may have access to this item. Find your institution then sign in to continue.
- Title
Non-centrosymmetric crystals of new N-benzylideneaniline derivatives as potential materials for non-linear optics.
- Authors
Souza, Talita Evelyn; Rosa, Iara Maria Landre; Legendre, Alexandre Oliveira; Paschoal, Diego; Maia, Lauro J. Q.; Dos Santos, Hélio F.; Martins, Felipe Terra; Doriguetto, Antonio Carlos
- Abstract
Three new N-benzylideneaniline derivatives [ p-nitrobenzylidene- p-phenylamineaniline (I), 2,4-dinitrobenzylidene- p-phenylamineaniline (II) and p-dinitrobenzylidene- p-diethylamineaniline (III)] containing electron-push-pull groups have been prepared. They present a planar N-benzylideneaniline core and neighbouring functional atoms, which are related through an efficient intramolecular charge transfer (CT). Two of the derivatives crystallize in non-centrosymmetric space groups, a necessary condition for non-linear optical (NLO) responses. The NLO properties were calculated for the molecular conformations determined by single-crystal X-ray diffraction as well as for the four molecules packed into each corresponding unit cell, using a quantum-chemical method at the cam-B3LYP/NLO-V level of theory. As expected from antiparallel face-to-face stacking through centrosymmetry, the main NLO descriptors - namely, the first hyperpolarizability (βtot) and its projection on the dipole moment direction (βvec) - are almost zero for the tetramer of derivative III. Interestingly, the calculated first hyperpolarizability decreases in the non-centrosymmetric unit-cell content of derivative II when compared to its single molecule, which may be related to its molecular pillaring, similar to that observed in derivative III. On the other hand, a desirable magnification of the NLO properties was found for packed units of derivative I, which may be a consequence of its parallel face-to-tail stacking with the CT vectors of all molecules pointing in the same direction. Moreover, the CT vector of compound I makes an angle of θ = 33.6° with its crystal polar axis, resulting in a higher-order parameter (cos3θ = 0.6) compared with the other derivatives. This is in line with the higher macroscopic second-order NLO response predicted for derivative I, βtot = 120.4 × 10−30 e.s.u.
- Subjects
CRYSTAL structure research; NONLINEAR optical techniques; INTRAMOLECULAR charge transfer; MOLECULAR conformation; X-ray diffraction
- Publication
Acta Crystallographica Section B: Structural Science, Crystal Engineering & Materials, 2015, Vol 71, Issue 4, p416
- ISSN
2052-5192
- Publication type
Article
- DOI
10.1107/S2052520615008859