1,4‐Bis((1H‐pyrrol‐2‐yl)methylene)thiosemicarbazide Complexes of Zn(II), Cd(II) and Hg(II): Single Source Precursor in Thermal Synthesis of Nanoparticle

Six complexes of Zn(II), Cd(II) and Hg(II) with sulphur containing Schiff base ligand, 1,4‐bis((1H‐pyrrol‐2‐yl)methylene)thiosemicarbazide in 1:1 and 1:2 ratio has been synthesized. Complexes were characterized by molar conductance measurement, elemental analyses, FT‐IR, ¹H‐NMR, and FAB/ESI‐Mass. The complexes were used as a single source precursor for the synthesis of ZnS/CdS/HgS nanoparticles by their thermal decomposition in the presence of different surfactants. The precursor: surfactant ratio and temperature plays important role in determining the size of the nanoparticles. The size and morphology of nanoparticles has been ascertained by UV‐Vis spectroscopy, XRD measurements and Transmission Electron Microscopy (TEM). Schiff base, complexes and nanoparticles were tested for antibacterial activity and MIC values against E. coli. The complexes were found more potent than the corresponding Schiff bases and nanoparticles.     

Field induced gradient simulations: a high throughput method for computing chemical potentials in multicomponent systems

We present a simulation method for direct computation of chemical potentials in multicomponent systems. The method involves application of a field to generate spatial gradients in the species number densities at equilibrium, from which the chemical potential of each species is theoretically estimated. A single simulation yields results over a range of thermodynamic states, as in high throughput experiments, and the method remains computationally efficient even at high number densities since it does not involve particle insertion at high densities. We illustrate the method by Monte Carlo simulations of binary hard sphere mixtures of particles with different sizes in a gravitational field. The results of the gradient Monte Carlo method are found to be in good agreement with chemical potentials computed using the classical Widom particle insertion method for spatially uniform systems.