XIV
h
International Conference on Molecular Spectroscopy, Białka Tatrzańska 2017
107
T4: O–10
Intramolecular proton-transfer fluorophores with donor-acceptor units
and in the presence of plasmonic resonance platforms
Illia E. Serdiuk
1
, Anna Synak
1
, Beata Grobelna
2
,
Ignacy Gryczynski
3
, and Piotr Bojarski
1
1
Faculty of Mathematics, Physics and Informatics, University of Gdańsk, 57 Wita Stwosza st., 80-308
Gdańsk, Poland, e-mail: illia.serdiuk@gmail.com
2
Faculty of Chemistry, University of Gdańsk, 63 Wita Stwosza st., 80-308 Gdańsk, Poland.
3
Center for Fluorescence Technologies and Nanomedicine, University of North Texas, Health
Science Center, 3500 Camp Bowie Boulevard, Fort Worth, Texas 76107, United States
There are various processes occurring in the excited state of fluorescent dyes. Among them
intramolecular proton transfer (ESIPT) represents photochemical reaction resulting in either
two-band fluorescence or abnormally red-shifted single-band fluorescence. Such fluorophores
are interesting from the point of application in biochemical analysis, biophysical investigations
and light-emitting devices. This presentation will concern spectral features of ESIPT
fluorophores i) containing donor-acceptor units and ii) at the conditions of fluorescence
enhancement by surface plasmonic resonance. The results of our investigations show that ESIPT
fluorophores can be successfully applied as multiparametric fluorescent indicators and single-
fluorophore white luminescent materials.
Keywords: fluorescence; ESIPT; plasmonic resonance, donor-acceptor systems
Acknowledgment
The research was financed by the BMN Grant (I.S.) and Polish National Science Centre (NCN) under Grant
No. 2015/17/B/ST5/03143 (A.S., B.G., I.G., P.B.).
References
[1] I. E. Serdiuk, A. Synak, B. Grobelna, I. Gryczynski, P. Bojarski, J. Phys. Chem. C 121 (2017) 636.
[2] I. E. Serdiuk, J. Phys. Chem. C 121 (2017) 5277.
XIV
h
International Conference on Molecular Spectroscopy, Białka Tatrzańska 2017
108
T6: O–1
Sample applications using combined
Raman + AFM/SEM/UV-VIS/XRF/FT-IR systems and devices
Ewa Korbiel
1
1
Irtech sp. z o.o., Wyżynna 8H, 30-617 Kraków, Poland, e-mail: ewa@irtech.pl
Raman spectroscopy and reflectance spectroscopy are two widely adopted methods to
determine the quality of the graphene layers. Combined UV-Vis reflectance and Raman micro-
spectroscopy could help to understand the characteristic of single and multiple layers of
graphene within a single microscopic region of interest. Raman microscopy is ideal for gem-
grade diamond authentication because Raman signal from diamond is very strong from its sp
3
carbon bond compared to sp
2
carbon bond in graphene and graphite. Also Raman spectrometer
can be used for in-situ and rapid detection of alcohol content and quantification of its alcohol
(ethanol) volume percentage in non-destructive way. In particular, it is possible to identify and
differentiate the Raman molecular fingerprint of methanol from ethanol in lab-prepared samples.
In addition, it is possible to precisely quantify the alcohol percentage of an unknown whisky
sample obtained from commercial products using a Raman calibration plot of alcohol-water
solution.
XIV
h
International Conference on Molecular Spectroscopy, Białka Tatrzańska 2017
109
T7: O–1
Mobility of acetone confined in zeolite nanocages
revealed by means of deuteron NMR spectroscopy
Zdzisław T. Lalowicz
1
, and Artur Birczyński
1
1
Institute of Nuclear Physics Polish Academy of Sciences, ul. Radzikowskiego 152, 31-342 Kraków,
Poland,e-mail: zdzislaw.lalowicz@ifj.edu.pl
Studies of molecular mobility are among classical applications of NMR spectroscopy. The
molecular motion shapes the NMR spectra, making the nuclear spin interactions time dependent,
and introducing different degrees of spectral averaging within the constraints imposed by the
transformation properties of the respective nuclear spin Hamiltonians. The choice of deuterons
as spin probes, characterized by a much stronger quadrupole interaction with suitable one-
particle transformation properties, guarantees more success, when compared to protons.
The doublet with the separation δ = (3/4)C
Q
, where C
Q
is the quadrupole coupling constant,
and asymmetry parameter η = 0, is observed for immobile deuterons. Uniaxial rotation of
molecular groups e.g. methyl groups or ammonium ions, provides characteristic spectra under
condition δτ
c
< 1, thus for correlation times τ
c
< 10
-6
s. Threefold rotation provides the doublet
with δ = (1/4)C
Q
. Exchange (π-jumps) about the twofold symmetry axis of e.g. ammonium ion
or water molecule, yields spectrum characterized by η = 1 [1]. Thus jumps of deuterons with
axially symmetric quadrupole interaction may yield a spectrum with η ≠0. This observation
guides our study, as such spectra were obtained for (CD
3
)
2
CO and ND
3
confined in cages of
zeolites at low temperature.
As a model system we take two methyl groups (immobile or rotating), performing jumps
with an amplitude φ on a cone with the opening angle Θ between threefold axes. Spectra were
calculated using WEBLAB package conveniently available via internet [2]. Spectra in a wide
range of angles provide a basis for fits to experimentally obtained ones. The angle Θ equals 58°
for (CD
3
)
2
CO, and with jump amplitude φ = 42° we get a good fit to the spectrum at 20 K for 86
molecules per unit cell in NaX zeolite with rotating methyl groups. Except of such torsional
jumps about the twofold axis of acetone, also oscillations by 66.7° of the molecular plane appear
on increasing temperature. Further on also oscillations by 79.5° about the axis perpendicular to
the molecular plane are evidenced.
Stepwise appearance of respective spectral components and their relative contributions
observed for NaX and NaY zeolites allow to point out differences in acetone bonding and local
structures. Acetone appears on Lewis acid sites, where the carboxyl oxygen of acetone interacts
with the Al atom of the zeolite framework, and a coordination adsorption complex is created.
Such geometry dominates in the case of NaX and NaY. Molecular reorientations and their
activation energy as well as temperature T
S
(below T
S
all molecules become localized) indicate
on stronger interaction of acetone with Lewis sites in the case of NaY.
Keywords: zeolite; deuteron NMR; molecular dynamics; acetone
Acknowledgment
The work was financed by the National Centre for Research and Development, contract No.
PBS2/A2/16/2013.
Sample preparation by Dr. Kinga Góra-Marek (Jagellonian University) is greatly acknowledged.
References
[1] Z. T. Lalowicz, S. F. Sagnowski, Z. Naturforsch. 46a (1991) 829.
[2] V. Macho, L. Brombacher, H. W. Spiess, Appl. Magn. Reson. 20 (2001) 405.
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