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Following
are the Faculty in the Center for Photochemical Sciences at Bowling
Green
State University and summaries of their research interests:
- Pavel
Anzenbacher, Jr., Associate Professor, Department of Chemistry
- George
S. Bullerjahn, Professor, Department of Biological Sciences
- John
R. Cable, Associate Professor, Department of Chemistry
- Felix
N. Castellano, Professor, Department of Chemistry
- Thomas
H. Kinstle, Distinguished Teaching Professor, Department of
Chemistry
- Ksenija
D. Glusac, Assistant Professor, Department of Chemistry
- Neocles
Leontis, Professor, Department of Chemistry
- H. Peter Lu, Professor and
Eminent Scholar in Photochemical Sciences, Department of Chemistry
- Douglas
C. Neckers, McMaster Distinguished Research Professor,
Department of Chemistry
- Michael
Y. Ogawa, Professor and Chair, Department of Chemistry
- Massimo Olivucci, Adjunct
Professor and Director, Laboratory for Computational Photochemistry,
Department of Chemistry
- Michael
A. J. Rodgers, Professor and Eminent Scholar in Photochemical
Sciences, Department of Chemistry
- Deanne
L. Snavely, Professor, Department of Chemistry; Associate Dean,
Graduate College
- Alexander
N. Tarnovsky, Assistant Professor, Department of Chemistry
- Bruno
Ullrich, Associate Professor, Department of Physics and
Astronomy
- R.
Marshall Wilson, Research Professor, Department of Chemistry
- Zhaohui Xu, Assistant Professor,
Department of Biological Sciences
- Weidong Yang, Assistant
Professor, Department of Biological Sciences
- Mikhail Zamkov, Assistant
Professor, Department of Physics and Astronomy
Pavel Anzenbacher, Jr.
Associate Professor, Department of Chemistry
pavel@bgsu.edu
 The
design and synthesis of novel pigments, dyes and photochromic materials
as
well as supramolecular aspects of molecular sensing is the focus of our
research
group. Our primary interest is in nanotechnology as it is applied to
molecular
sensing with particular attention being devoted to the sensing of
anionic
analytes.
We are also interested in the design aspects of
artificial pigments and dyes, as well as the invention and development
of
general tactics and strategies for the synthesis of structural
analogues
of porphyrin macrocycles and related pyrrole-based systems.
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George S. Bullerjahn
Professor, Department of Biological Sciences
bullerj@bgsu.edu
 Our
work is currently focused on the regulation of
nutrient-stress-inducible
genes in cyanobacteria. We have identified genes and gene products
inducible
under nutrient (N, S, P) limitation and stationary phase conditions,
and
this work may help define universal rules in the adaptation of bacteria
to
changing and extreme environments.
Additionally, we are working
on understanding the structure and dynamics of photosynthetic complexes
in
the chl a/b containing prokaryote Prochlorothrix. Such work will help
in
the understanding of how phototrophs can colonize low light habitats.
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John R. Cable
Associate Professor, Department of Chemistry
cable@bgsu.edu
 Our
research is focused on determining the structures of conformationally
flexible
molecules and the effect that solvation and hydrogen bonding has on
these
structures. To carry out these investigations we make use of
vibrationally
resolved electronic spectroscopy in the ultracold environment of a
supersonic
jet expansion. Electronic spectroscopy permits structural information
to
be obtained on both ground and excited electronic states through
analysis
of the resolved vibrational structure that appears under these
conditions.
We are currently investigating a number of phenyl-substituted
amines and amides. These types of molecules form strong hydrogen bonds
with
a variety of partners, including water, and have the potential to act
as
both donors and acceptors. By studying hydrogen bonded clusters at high
spectral
resolution it is possible to determine the mode of binding between the
solute
and solvent as well as to characterize the structural perturbations
that
arise from the strong interaction.
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Felix N. Castellano
Professor, Department of Chemistry
castell@bgsu.edu
 Our current research
focus involves the photochemistry and photophysics
of metal-organic chromophores, where the proper combination of metal
complex and organic subunit(s) yield new luminescent molecules or
assemblies
with distinct properties and potentially useful functions. Most of the
chromophores of interest are centered around platinum(II) and
ruthenium(II)
coordination and organometallic complexes. We are interested in
developing
new synthetic methodologies for these molecules, including the
utilization
of closed and open vessel microwave synthesis. From the fundamental
perspective,
we are interested in the interplay of closely-lying excited states and
the influence these interactions have on the resulting photophysics.
These
processes are investigated with a battery of static and time-resolved
spectroscopic techniques, the latter revealing excited state dynamics
evolving from
the femtosecond regime to milliseconds. We have recently
developed
photochemical schemes which result in low power photon upconversion;
shifting
the energy of incident radiation to higher energy. This approach also
provides a means to access traditional ultraviolet-driven photochemical
reactions using visible photons. We are also working on a variety of
alternative
energy-relevant projects including dye sensitized solar cells and
photocatalytic
hydrogen
production.
Recent publication in Chemical Communications
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Ksenija D. Glusac
Assistant Professor, Department of Chemistry
kglusac@bgsu.edu
 Our group
is interested in the study of coupled proton and electron motion in
hydrogen-bonded D/A systems. Electron transfer (ET) mediated by
hydrogen
bonds (H-bonds) is essential to the function of redox proteins in many
biological
processes, particularly photosynthesis and respiration. Apart from
providing
a medium for ET, H-bonds in ET proteins have other functions. For
example,
ET in biological systems is often accompanied with a proton transfer
along
a certain H-bonded surface with the goal to achieve catalytic activity
or
drive proton pumps. Even though some insight into the general ET and
proton
transfer pathways in proteins has been obtained, a full understanding
of
the coupled effects that proton and electron motion have on each other
is
yet to be achieved.
Apart from its significance in
biological
systems, the understanding of ET through H-bonded systems will be
valuable
for the development of future devices. For example, the design of an
efficient
solar cell requires a donor/acceptor (D/A) system with a long-lived
charge
separated state. To achieve this goal, a specific H-bonded D/A system
can
be envisioned in which the initial charge separation induces the proton
motion
along the H-bonded surface and makes the charge recombination highly
inefficient.
In other words, the H-bonded surface could act as a unidirectional gate
for
the electron flow in D/A systems.
In order to obtain information on
both
electron and proton dynamics, we use two techniques: VIS pump-VIS probe
and
VIS pump-IR probe spectroscopy. After excitation using a VIS pump beam,
the
ET processes is studied by probing the transient species in the VIS
spectral
region, while the proton motion is observed by probing the vibrational
modes
of the transient species in the IR region. The model compounds are
designed
with the goal to elucidate the mechanism of coupled electron and proton
motion
both along H-bonded D/A systems and along H-bonded D/water/A systems.
Thomas H. Kinstle
Distinguished Teaching Professor, Department of Chemistry
tkinstl@bgsu.edu
 Our program in natural
products/bio-organic
chemistry is concerned with the synthesis and biological evaluation
analogs
of plant derived phenolic compounds known to be inhibitors of tumor
formation.
Ellagic acid, present in various fruits and vegetables, particularly
strawberries,
is a planar biaryl polyphenol. Epigallocatechin gallate (EGCG) is
a flavanoid
polyphenol found in high concentration in brewed green tea.
Analogs, chosen
on the basis of computerized molecular modeling studies, are being
synthesized.
A long- term program in the chemistry of strained bicyclic
ring compounds
is proceeding in the areas of synthesis, mechanism and spectroscopy. We
are
particularly interested in partially fluorinated bicyclo[2.1.0]
pentanes.
Flash vacuum pyrolysis techniques have allowed us to synthesize several
novel
non-natural molecules.
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Neocles
Leontis
Professor, Department of Chemistry
leontis@bgsu.edu
 Nucleic Acids (DNA and RNA) play diverse roles in living
organisms. Not
only do they encode genetic information but they actively participate
in
its readout from transcription to translation, including splicing,
editing,
and regulation at each stage. Single-stranded DNA and RNA molecules
fold
into complex 3-dimensional structures to carry out these roles. We are
investigating
the logic of the 3D architecture of these molecules using an integrated
biophysical,
biochemical, and bioinformatic approach. These complex structures are
able
to specifically bind other molecules, including potential drug
molecules.
Photosensitizers that can specifically bind DNA or RNA molecules have
tremendous
potential for overcoming present limitations of photodynamic therapy,
by
directing damage to molecules specific to the target cells. We are
investigating
the binding of potent photosensitizers to complex nucleic acids using
biophysical
and biochemical methods.
H. Peter Lu
Eminent Scholar in Photochemical Sciences, Department of
Chemistry
hplu@bgsu.edu
 Our research is
focused on the use of single molecule techniques to understand
molecular dynamic processes
and the effects of the local environment on these processes.
We have been developing and applying time-resolved,
nanoscale site-specific, single molecule methods that are
an effective alternative to conventional methods, providing information
under conditions most applicable to the
natural processes underlying the area of research
interest. Single-molecule approaches are useful and
unique in studying heterogeneous and complex systems because the
inhomogeneity can be identified and/or removed by studying one molecule
at a time. Single molecules and molecular complexes can be observed as
they traverse a wide range of energy states in real-time and the effect
of this ever changing "system configuration" on chemical/biological
reactions and other dynamical processes can be mapped.
Our current research work has been focused on (1) conformational
dynamics and reaction in proteins and protein complexes under
physiological conditions, and our long-term goal is to study
single-molecule protein conformational dynamics and reactions in living
cells; and (2) inhomogeneous interfacial chemical and biological
reaction dynamics in solar energy conversion, bioremediation, and
environmental systems, focusing on fundamental understanding of the
controlling physical and chemical properties, such as, Franck-Condon
coupling and barrier, vibrational and solvent relaxation energetics,
molecular distributions, redox states identification, and molecular
motions.
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Douglas C. Neckers
McMaster Distinguished Research Professor, Department of Chemistry
neckers@photo.bgsu.edu
 One
area of research uses visible light photoinitiators synthesized in my
laboratory
to form photopolymers. We want to develop new photopolymerization
systems
and understand the molecular details of how polymerization occurs after
the
absorption of light. We are also interested in controlling
polymerization
in all dimensions from the surface of a developing system. This has
many
applications such as three-dimensional imaging and direct laser writing.
In the general area of laser-initiated photopolymerization, we
are concerned with:
- Investigating
the photochemistry of molecules which initiate polymerization by either
free
radical mechanisms or cationic mechanisms after they absorb radiation;
- Synthesis of new photoinitiators and new monomers, which
can be photopolymerized;
- Development of new photosensitive materials and composite
materials; and,
- Studying the process of photopolymerization by new
transient spectroscopic techniques.
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Michael Y. Ogawa
Professor and Chair, Department of Chemistry
mogawa@bgsu.edu
 Our
group is developing a new class of hybrid inorganic/biological
materials
possessing novel photochemical properties. In one project we are
using
the principles of “metalloprotein design” to prepare a new class of
miniature
metalloproteins containing luminescent Cu(I) centers. The
photophysical
properties of these systems have been found to mimic many features
found
in natural photosynthetic reaction centers and can be used to develop
new
routes towards solar energy conversion. A related project
uses
supramolecular coordination chemistry to direct the assembly of novel
peptide
structures. We have found that such metal-mediated peptide
assemblies
possess a diverse range of morphologies ranging from nanometer-scale
hollow
spheres to nano-cylinders, making them possible candidates for drug
delivery
vehicles. Thus, a central theme of our laboratory is to combine
inorganic
coordination chemistry/photochemistry with protein design in order to
prepare
new types of hybrid materials which possess potentially useful chemical
properties.
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Massimo Olivucci
Adjunct Professor; Director, Laboratory for Computational Photochemistry,
Department of Chemistry
molivuc@bgsu.edu
 We
use conventional and novel computational tools to investigate the
reactivity of organic and biological molecules in their electronically
excited states. One major target of our work is the mapping of the
photon-induced "force field" which sets an equilibrium molecular
structure into motion in realistic molecular environments (e.g. in
solution or in a protein cavity). This force field can be calculated
and represented in terms of photochemical reaction paths: ie. paths
that start on an excited state potential energy surface and end on the
ground state energy surface. Photochemical reaction paths comprise
mechanistic elements that are not involved in the description of
thermal reactions. These correspond to real crossings of different
potential energy surfaces. For photochemical reactions prompted by
direct irradiation these crossings often correspond to conical
intersections that are regarded as the photochemical analogues of
transition states. Given the central role of photochemical reaction
paths and conical intersections (as well as singlet/triplet surface
crossings) in the investigation of the excited state reactivity of
proteins (e.g. biological photoreceptors) or solvated molecules (e.g.
dyes in solution), we also develop computational strategies based on a
combination of ab-initio quantum chemical methods and molecular
mechanics methods that allow to study the effects of light irradiation
on complex molecular systems.
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Michael A. J. Rodgers
Eminent Scholar in Photochemical Sciences, Department of Chemistry
rodgers@bgsu.edu
 Dr.
Rodgers' research interests may be broadly classified as studies in
photodynamics.
These studies are broken down roughly into the following categories:
- Excited state dynamics of tetrapyrrole
macrocycles.
- Photodynamic damage in biology.
- Energy transfer involving oxygen.
- Electron transfer in proteins and
peptides.
- The design, assembly and use of
high-technology instrumentation for transient spectroscopy.
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Deanne L. Snavely
Professor, Department of Chemistry
Associate Dean, Graduate College
snavely@bgsu.edu
 We
are using vibrational overtone pumping, which involves selectively
pumping
vibrational states using visible laser light, to answer fundamental
questions
about the effects of vibrational and rotational energy on the rate of
chemical
reaction and about the competition between reaction and collisional
deactivation.
The study of the nature of highly excited vibrational states and their
effect
on reactivity is important because all thermal reactions involve these
excited
vibrational states. The laser wavelength can be tuned to excite a
specific
vibrational motion in the molecule. Three chemical reactions are under
study:
the isomerization of methyl isocyanide to acetonitrile, the ring
opening
of methyl cyclopropene, and the hydrogen shift reaction of
methylcyclopentadiene.
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Alexander N. Tarnovsky
Assistant Professor, Department of Chemistry
atarnov@bgsu.edu
 The focus
of our research interests is two-fold:
- Developing a molecular-level understanding of the
dynamics of chemical reactions occurring in solution, and;
- Gaining a deep, detailed insight into the dynamics
and mechanisms of ultrafast (femto- and picosecond) photoinduced
processes.
In our research, we use state-of-the art experimental methods of
ultrafast, time-resolved spectroscopy.
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Bruno
Ullrich
Associate Professor, Department of Physics and Astronomy
bruno@kottan-labs.bgsu.edu
 The
research of Ullrich's group focuses mainly on two subjects,
optoelectronic
devices (ODs) and thin film preparation by pulsed laser deposition
(PLD).
With
ODs, the linear and nonlinear optical properties of inorganic and
organic
semiconductors are investigated by various techniques such as
photoluminescence,
photocurrent, two-photon absorption, ultrafast spectroscopy, pump-probe
and
z-scan measurements. The experiments are carried out on bulk material,
heterostructures
and thin films as well.
By using PLD, thin semiconducting
films with outstanding optical and optoelectronic features are formed.
PLD
is a very versatile and promising technique and meets the future
requirements
of material preparation. Specifically, the influence of laser light
intensity
and photon energy used for the deposition process on the film
properties
is studied in detail.
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R. Marshall Wilson
Research Professor, Department of Chemistry
rmw@bgsu.edu
 Our
research interests are directed towards photochemical application
of lasers, primarily argon ion lasers, and fall into two broad
categories:
the laser synthesis of new materials and the development of reagents
for
the photochemical manipulation of biological systems. These
include:
- The
use of CW laser plasmas to prepare carbon bowls, Bucky Bowls and the
study
of the properties of these bowl-shaped “aromatic” hydrocarbons.
- The development of new reagents for the photochemical
cross-linking of nucleic acids, primarily RNA, with proteins.
- The development of new reagents for the photochemical
cleavage of nucleic acids, primarily RNA.
- The
development of the aforementioned two techniques to study the
interactions
between nucleic acids and proteins using mass spectrometry to obtain
detailed
structural information about the nature of these interactions
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Zhaohui Xu
Assistant Professor, Department of Biological Sciences
zxu@bgsu.edu
 Use of genetic
and biochemical approaches to develop microbial systems that
can be applied to environmental processes, such as remediation of
hazardous
substances, development of detection or monitoring systems, and
production
of high value products from agricultural or industrial by-products or
wastes.
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Yang, Weidong
Assistant Professor, Department of Biological Sciences
wyang@bgsu.edu
 My research
focuses on three major projects: nucleocytoplasmic trafficking
mechanism, nuclear envelope disassembly and assembly mechanisms and
application
of quantum dots in biological systems. Methodologies and techniques in
my
lab include single molecule methods, biochemistry, photochemical
spectroscopy,
advanced optical imaging methods and nanotechnology.
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Zamkov,
Mikhail
Assistant Professor, Department of Physics and Astronomy
zamkovm@bgsu.edu
 Our research focuses on
the electronic, chemical and optical properties of
hybrid nanoscale materials prepared with sub-nanometer precision by
means
of colloidal syntheses. Specifically, experimental work in our group
addresses
four major areas: (1) synthesis and characterization of novel nanoscale
building
blocks, (2) elucidation of their fundamental optoelectronic properties,
(3)
design and demonstration of functional nanoscale devices and integrated
nanosystems,
and (4) exploration of the interface/communication between biological
systems
and nanoscale devices. This research is highly interdisciplinary,
involving
concepts and techniques from biology, chemistry, physics and the
engineering
sciences to achieve our goals.
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