Laboratóriumok

Laboratory for Weak Molecular Interactions

In this laboratory the methods of spectroscopy, thermodyanamics and theoretical approaches are applied to study the weak molecular interactions.

Weak molecular interactions plays determining role in the nature due to their reversible behavior they are able to control many complex systems including living organizations. Through the background electric field created by the solvent molecules around solutes, in condensed phase the strength of such interactions preferably controlled by the first coordination sphere of the solvation shells of molecules interacted. Therefore these weak interactions are highly controllable by varying the composition and structure of the solvation shell. Our preliminary results show unique properties of the solvation shells formed in binary solutions which composition differs considerably from the composition of the bulk. Furthermore, the composition of the solvation shell shows significant change within a range while the variation of the molar composition of bulk solutions less than about 0.01 of molar fraction. This property means that very slight change in the composition of the bulk molecular environment result in huge change in the structure and composition of the solvation shells raising large change of the complex stabilities and enormously shifts the chemical equilibriums in the system. Further the unexpected thermodynamic behaviors, our previous investigations highlighted solvent-dependent inhomogeneous distribution of the kinetic energy on molecules possessing aromatic moieties. This property affects significantly the kinetics of the chemical reactions driven by weak molecular interactions. Due to the preliminary observations listed above via controlling the environment we are able to control at least a particular family of weak molecular interactions which however plays important role in very wide scale of chemistry and biochemistry.



Location :
University of Pécs, Department of General and Physical Chemistry
H-7624 Pécs, Ifjúság 6, Hungary

Contact :
Dr. Sándor Kunsági-Máté
head of the department
kunsagi [k] gamma [p] ttk [p] pte [p] hu


Instruments:

Fluorolog τ3 spectrofluorimeter (Jobin-Yvon/SPEX)
PhotoLuminescence and related techniques (PL, lifetime, anisotropy, anisotropy decay, solvent relaxation).

Latest investigations performed:

i)  Host - guest interactions of calixarenes towards aromatic neutral guest phenols and benzotrifluoride molecules, interactions of crown ethers with alkali metal ions

ii)  Controlling the folding of Bovin Serum Albumine via slight change in the composition of bulk binary solutions

iii)  Competitive interactions of flavons and flavonols with Ochratoxin A towards Human Serum Albumin

iv)  Interactions of anthocyanines with polyphenols in red wines as model for water-ethanol mixtures

vi)  Structure of common solvents and solvation shells in solvent mixtures


Fluorolog tau3





Labram HR confocal Raman microscope /Jobin-Yvon/ combined with an AFM microscope
Surface Enhanced Raman and Tip Enhanced Raman measurements

Latest investigations performed:

v)  Association of carbon nanotubes and their adsorption onto a nanostructured wide band gap CeO2 semiconductor surfaces.

Labram HR confocal Raman microscope /Jobin-Yvon/ combined with an AFM microscope





Nano II. DSC (SETARAM)
Different Scanning Calorimetry and related methods

Latest investigations performed:

ii)  Controlling the folding of Bovin Serum Albumine via slight change in the composition of bulk binary solutions

Nano II. DSC (SETARAM)





UV-Vis Photometry

Latest investigations performed:

i)  Host - guest interactions of calixarenes towards aromatic neutral guest phenols and benzotrifluoride molecules, interactions of crown ethers with alkali metal ions

iii)  Competitive interactions of flavons and flavonols with Ochratoxin A towards Human Serum Albumin

iv)  Interactions of anthocyanines with polyphenols in red wines as model for water-ethanol mixtures

UV-Vis Photometry