There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality.

Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …

I and i

Because of its fundamental importance in many branches of science, hydrogen bonding is a subject of intense contemporary research interest. The physical and chemical properties of hydrogen bonds in the ground state have been widely studied both experimentally and theoretically by chemists, physicists, and biologists. However, hydrogen bonding in the electronic excited state, which plays an important role in many photophysical processes and photochemical reactions, has scarcely been investigated.Upon electronic excitation of hydrogen-bonded systems by light, the hydrogen donor and acceptor molecules must reorganize in the electronic excited state because of the significant charge distribution difference between the different electronic states. The electronic excited-state hydrogen-bonding dynamics, which are predominantly determined by the vibrational motions of the hydrogen donor and acceptor groups, generally occur on ultrafast time scales of hundreds of femtoseconds. As a result, state-of-the-art femtos...

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Hydrogen Bonding in the Electronic Excited State

Green-synthesized nanocatalysts and nanomaterials for water treatment: Current challenges and future perspectives.

A review on the chemistry, coordination, structure and biological properties of 1-(acyl/aroyl)-3-(substituted) thioureas

Five thiourea derivative ligands and their Ni 2+ and Cu 2+ complexes have been synthesized. The compounds were screened for their in vitro anti-bacterial activity using Gram-positive bacteria (two different standard strains of Staphylococcus aureus , Staphylococcus epidermidis , Enterococcus faecalis , Streptococcus pyogenes , Bacillus cereus ) and Gram-negative bacteria ( Esherichia coli , Pseudomonas aeruginosa , Enterobacter cloacae , Proteus vulgaris , Enterobacter aerogenes ) and in vitro anti-yeast activity ( Candida albicans , Candida krusei , Candida glabrata , Candida tropicalis , Candida parapsilosis ). The minimum inhibitory concentration was determined for all ligands and their complexes. In vitro anti-yeast activity of both ligands and their metal complexes is greater than their in vitro anti-bacterial activity. The effect of the structure of the investigated compounds on the antimicrobial activity is discussed. Keywords: Thiourea derivatives; Complexes; Antibacterial activity; Antifungal activity;

http://faculty.uncfsu.edu/cakbay/molecules.pdf

Antimicrobial Activity of Some Thiourea Derivatives and Their Nickel and Copper Complexes

The molecular structure and vibrational spectra of 2-chloro-N-(diethylcarbamothioyl)benzamide by Hartree–Fock and density functional methods

A novel thiourea derivative, N -(6-methylpyridin-2-yl-carbamothioyl)biphenyl-4-carbox amide, is synthesized and characterized by elemental analysis, FT-IR, NMR and single crystal X-ray diffraction study. There are two independent molecules A and B in the asymmetric unit. The short bond lengths of the C-N bonds in the central thiourea fragment indicate partial double bond character in this fragment of the title compound. These results can be explained by the existence of resonance in this part of the molecule. Each A and B molecule is stabilized with an intramolecular N-H•••O hydrogen bond which results in the formation of a pseudo six membered ring. In addition, the independent molecules are linked into a chain along the c axis by weak N-H•••S intermolecular hydrogen bonds. The conformational behavior and structural stability of the optimized geometry of the title compound were also investigated by utilizing ab- initio calculations with 6-31G* basis set at HF, BLYP, and B3LYP levels. The calculated parameters are in good agreement with the corresponding X-ray diffraction values.

/pdf/theoretical-and-experimental-studies-on-n-6-methylpyridin-2-1vk077y144.pdf

Theoretical and experimental studies on N-(6-methylpyridin-2-yl-carbamothioyl)biphenyl-4-carboxamide

N,N-di-n-propyl-N′-(2-chlorobenzoyl)thiourea (HL1) (1), N,N-diphenyl-N′-(2-chlorobenzoyl)thiourea (HL2) (2), and their NiII, CoII, CuII, ZnII, PtII, CdII and PdII complexes have been synthesized and characterized. HL1 and its copper complex were characterized by single-crystal X-ray diffraction methods. The ligands coordinate as bidentates yielding essentially neutral complexes of the type [ML2]. The complexes were screened for their in vitro antibacterial, antifungal activities and toxicity. All compounds showed antimicrobial activity, but antibacterial efficacy is greater than antifungal activity.

Synthesis, characterization and antimicrobial activities of transition metal complexes of N,N -dialkyl- N′ -(2-chlorobenzoyl)thiourea derivatives

4-Bromo-N-(di-R-carbamothioyl)benzamide (R = methyl, ethyl, n-propyl, n-butyl and phenyl) ligands and their Ni(II) and Cu(II) complexes have been synthesized and characterized by elemental analyses, FT-IR and 1H-NMR spectroscopy. The crystal and molecular structure of bis(4-bromo-N-(di-n-propylcarbamothioyl)benzamido)nickel(II) has been determined from single crystal X-ray diffraction data. It crystallizes in the triclinic, space group P 1, Z = 2 with a = 9.286(2) A, b = 13.215(3) A, c = 14.125(3) A, α = 64.180(5)°, β = 85.483(6)°, γ = 83.067(5)°, V = 1548.3(7) A3 and D Calcd = 1.594 mg m−3. Loss of the N–H proton resonance and the N–H stretching vibration and the shift of the ν C=O and ν C=S stretching vibrations confirm formation of the metal complexes. These studies have shown that the metal complexes are neutral cis-[ML2].

Synthesis and characterization of Cu(II) and Ni(II) complexes of some 4-bromo- N -(di(alkyl/aryl)carbamothioyl) benzamide derivatives

Green synthesis of silver and palladium nanoparticles using Lithodora hispidula (Sm.) Griseb. (Boraginaceae) and application to the electrocatalytic reduction of hydrogen peroxide

Gun Binzet

Papers

The molecular structure and vibrational spectra of 2-chloro-N-(diethylcarbamothioyl)benzamide by Hartree–Fock and density functional methods

Theoretical and experimental studies on N-(6-methylpyridin-2-yl-carbamothioyl)biphenyl-4-carboxamide

Synthesis, characterization and antimicrobial activities of transition metal complexes of N,N -dialkyl- N′ -(2-chlorobenzoyl)thiourea derivatives

Synthesis and characterization of Cu(II) and Ni(II) complexes of some 4-bromo- N -(di(alkyl/aryl)carbamothioyl) benzamide derivatives

Green synthesis of silver and palladium nanoparticles using Lithodora hispidula (Sm.) Griseb. (Boraginaceae) and application to the electrocatalytic reduction of hydrogen peroxide