In order to find eco-friendly materials for different applications an important research effort was devoted to the materials science in the last decade. A particular attention attracted the deoxyribonucleic acid (DNA). The interest is due to its versatility, biodegradability, abundance and their origin from renewable sources. DNA based new materials, functionalized with hexadecyltrimethylammonium chloride (CTMA) and aromatic compounds were prepared. Solutions with two different concentrations of aromatic compounds were obtained in butanol. The obtained, new complexes were processed into good optical quality thin films by spin coating method. Films were deposited on glass substrates and characterized for their spectroscopic, linear and nonlinear optical properties. The third-order nonlinear optical (NLO) properties of thin films were determined by the optical third-harmonic generation technique at 1 064.2 nm fundamental wavelength. The obtained materials, with improved fluorescence efficiency, present a potential interest for application in photonics.
Formyl-methoxy derivatives of [2.2]paracyclophane (pCp) have been synthesized and studied by optical spectroscopy
as well as the X-ray diffraction method. These molecules crystallize in acentric space groups. The efficiency of SHG
ability of these compounds was measured by the powder technique at 1064 nm fundamental wavelength and average
NLO susceptibility for some of them was found comparable with such well-known NLO crystal as NPP. The
calculations of molecular and crystalline nonlinearities within density functional theory using M052X/6-31+G* level of
approximation were also conducted for the considered series of compounds.
The series of novel unsymmetrical β--diketones substituted by functional groups with different donor-acceptor properties,
as well as of their lanthanide complexes have been synthesized for the first time. The optical properties of these
[2.2]paracyclophane-derived ligands and the lanthanide complexes were studied by UV-visible and luminescence
spectroscopy. The energy of absorption maximum of these
β--diketones correlates with donor-acceptor properties of
functional groups and a size of the conjugated system. All
β--diketonates synthesized exhibit broad emission spectra with
red shifted maxima in comparison with isolated [2.2]paracyclophane moiety. The designed blue-emitting unsymmetrical
β-diketones act as very efficient sensitizers of the Eu3+ emission with excitation wavelength up to 450 nm. Nonlinear
optical properties have been studies for some β--diketones as well. Their average NLO susceptibility was found
comparable with that of such well known NLO crystal as PNP.
The lanthanide compounds containing unsymmetrical β-diketone with [2.2]paracyclophane moiety in particular the
europium complex with three [1-(4-[2.2]paracyclophanyl)]-3-phenylpropane-1,3-dione and 1,10-phenanthroline has been
synthesized for the first time. The optical properties of [2.2]paracyclophane-derived ligands (symmetrical β-diketones
and their respective N-phenylimines) as well as those of the europium complex were studied by UV-visible and
luminescence spectroscopy. The diastereomers (racemic chiral, (R*,R*)- and achiral meso, (R,S)-) of the β-diketones and
their respective N-phenylimines exhibit quite identical absorption spectra with intense broad band centered at 360 and
380 nm, respectively. The designed blue-emitting unsymmetrical β-diketone acts as a very efficient sensitizer of the EuIII
emission and does so in the near-UV region. The introduction of [2.2]paracyclophane moiety in the β-diketones allows
to expand the excitation wavelength of the lanthanide complex up to 500 nm and to obtain the relatively high overall
quantum yield for the europium ion.