TY  - JOUR
A1  - Gharabekyan, Hrant H.
A1  - Koetz, Joachim
A1  - Poghosyan, Armen H.
T1  - A protonated L-cysteine adsorption on gold surface
BT  - a molecular dynamics study
JF  - Colloids and surfaces : an international journal devoted to the principles and applications of colloid and interface science ; A, Physicochemical and engineering aspects
N2  - The adsorption of protonated L-cysteine onto Au(111) surface was studied via molecular dynamics method. The detailed examination of trajectories reveals that a couple of picoseconds need to be strongly adsorbed at the gold surface via L-cysteine's sulfur and oxygen atoms. The average distances of L-cysteine's adsorbed sulfur and oxygen from gold plane are-2.7 angstrom and-3.2 angstrom, correspondingly. We found that the adsorption of L-cysteine takes place preferentially at bridge site with possibility of-82%. Discussing the conformation features of protonated L-cysteine, we consider that the most stable conformation of protonated L-cysteine is "reverse boat" position, where sulfur and oxygen pointed down to the gold surface, while the amino group is far from the gold surface.
KW  - MD simulations
KW  - gold surface
KW  - GOIP
KW  - l-cysteine
KW  - adsorption
KW  - protonation
Y1  - 2021
U6  - https://doi.org/10.1016/j.colsurfa.2021.127452
SN  - 0927-7757
SN  - 1873-4359
VL  - 629
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Otter, Dirk
A1  - Mondal, Suvendu Sekhar
A1  - Alrefai, Anas
A1  - Krätz, Lorenz
A1  - Holdt, Hans-Jürgen
A1  - Bart, Hans-Jörg
T1  - Characterization of an isostructural MOF series of Imidazolate Frameworks Potsdam by means of sorption experiments with water vapor
JF  - Nanomaterials
N2  - Sorption measurements of water vapor on an isoreticular series of Imidazolate Frameworks Potsdam (IFP), based on penta-coordinated metal centers with secondary building units (SBUs) connected by multidentate amido-imidate-imidazolate linkers, have been carried out at 303.15 K. The isotherm shapes were analyzed in order to gain insight into material properties and compared to sorption experiments with nitrogen at 77.4 K and carbon dioxide at 273.15 K. Results show that water vapor sorption measurements are strongly influenced by the pore size distribution while having a distinct hysteresis loop between the adsorption and desorption branch in common. Thus, IFP-4 and -8, which solely contain micropores, exhibit H4 (type I) isotherm shapes, while those of IFP-1, -2 and -5, which also contain mesopores, are of H3 (type IV) shape with three inflection points. The choice of the used linker substituents and transition metals employed in the framework has a tremendous effect on the material properties and functionality. The water uptake capacities of the examined IFPs are ranging 0.48 mmol g(-1) (IFP-4) to 6.99 mmol g(-1) (IFP-5) and comparable to those documented for ZIFs. The water vapor stability of IFPs is high, with the exception of IFP-8.
KW  - material characterization
KW  - water vapor
KW  - adsorption
KW  - hysteresis
KW  - Imidazolate Frameworks Potsdam
Y1  - 2021
U6  - https://doi.org/10.3390/nano11061400
SN  - 2079-4991
VL  - 11
IS  - 6
PB  - MDPI
CY  - Basel
ER  -