NOPR Collection:

A new single pulse method for the measurements of photosensitized singlet oxygen quantum yield

2016-07-20T04:57:59Z

Title: A new single pulse method for the measurements of photosensitized singlet oxygen quantum yield Authors: Venkatesan, R; Tamijselvy, S; Periasamy, N; Rajendiran, T M; Rao, P S; Srivastava, T S Abstract: A new simpler relative method for estimating photosensitized singlet oxygen quantum yield has been developed. In this method a strong depletion signal is observed when porphyrin (2μM) and l,3-diphenylisobenzofuran (DPBF, 500 μ M) are irradiated using second harmonic 532 nm Nd-YAG laser pulse and monitored at 410 or 415 nm by a ultraviolet filtered white light. The observed depletion is attributed to the reaction of DPBF with sensitized singlet oxygen. The amplitude of the depletion signal is related directly to the singlet oxygen sensitization yield. Appropriate kinetic equations have been derived to relate the change in the absorbance of DPBF and singlet oxygen quantum yield. The singlet oxygen quantum yields of fifteen porphyrins and metalloporphyrins have been investigated in dimethylformamide solution. The results are compared with the quantum yields obtained by the usual kinetic run experiments. The results are found to match exceedingly well in the two methods. Page(s): 346-349

Synthesis and characterization of chlorodibenzyltin(IV) complexes with N,N-dialkyl dithiocarbamate ligands and crystal structure of (PhCH₂)₂SnCl(S₂CNMe₂)

2016-07-20T05:06:44Z

Title: Synthesis and characterization of chlorodibenzyltin(IV) complexes with N,N-dialkyl dithiocarbamate ligands and crystal structure of (PhCH₂)₂SnCl(S₂CNMe₂) Authors: Yin, Handong; Ma, Chunlin; Wang, Yong Abstract: Thirteen chlorodibenzyltin(IV) complexes with N,N-dialkyl dithiocarbamate ligands have been synthesized by the reaction of dibenzyltin dichloride with N,N-dialkyl dithiocarbamates in 1:1 stoichiometry and characterized by elemental analysis, UV, I R and ¹H NMR. The crystal structure of (PhCH₂)₂SnCl(S₂CNMe₂) has been determined by X-ray single crystal diffraction. The crystallographic data are as follows: triclinic, space group P-1, a=7.5750(15) Å, b= 10.615(2) Å, c= 12.059(2) Å, α=95.053(3)^o, β=95.539(4)^o, γ=99.113(4)^o, Z=2, V=947.6(3) Å, Dx= 1.600g/cm^-3, μ= 1.705mm^-1, F(000)=456, R₁=0.0409, wR₂=0. 1194(I≥ ~2σ(I). The structures consist of discrete molecules containing five-coordinate tin atoms in a seriously distorted trigonal bipyramidal configuration. The molecules are packed in the unit cell as weakly-bridged dimers. Page(s): 342-345

Synthesis, magnetic and spectral studies of some new mixed-ligand nitrosyl complexes of chromium(I)

2016-07-20T04:51:15Z

Title: Synthesis, magnetic and spectral studies of some new mixed-ligand nitrosyl complexes of chromium(I) Authors: Maurya, R C; Pandey, A; Verma, R Abstract: The synthesis and characterization of some new mixed-ligand nitrosyl chromium(I) complexes (having (CrNO}^5* electron configuration) of the general formula [Cr(NO)(acac)₂(L)] , [where L = benzothiazole (BZT), 2-(2'-pyridyl)benzimidazole (PBZL), 2- hydroxymethylpyridine (2-HMP), 3-hydroxymetlylpyridine (3-HMP), o-anisidine (ANS) or N,N'-dimethylanilinc (NNDA)] have been carried out. The compounds having chromium(I) in a lowspin d⁵ configuration have been characterized by elemental analyses, molar conductance. TGA, magnetic measurements, elcctron spin resonance and infrared spectral studies. Page(s): 339-341

Synthesis and characterization of epoxy resin in the presence of p-acetylbenylidene triphenylarsoniumylide-mercuric chloride complex

2016-07-20T04:55:37Z

Title: Synthesis and characterization of epoxy resin in the presence of p-acetylbenylidene triphenylarsoniumylide-mercuric chloride complex Authors: Pandey, Saurabh; Srivastava, A K Abstract: p-Acetylbenylidene triphenylarsoniumylide-mercuric chloride complex modifies and also has autocatalytic curing properties for epoxy resin. The degree of cure (αʹ), percentage crystallinity and glass transition temperature (Tg) of the modified resin, investigated by differential scanning calorimetry, are 1.03, 91 % and 298°C respectively. The TGA technique has been used to calculate the activation energy and the order of reaction, which are 97 kJ/mol and one respectively. The SEM analysis shows presence of Hg (40%) in the epoxy resin. Page(s): 333-338

NOPR Collection:

A new single pulse method for the measurements of photosensitized singlet oxygen quantum yield

Synthesis and characterization of chlorodibenzyltin(IV) complexes with N,N-dialkyl dithiocarbamate ligands and crystal structure of (PhCH2)2SnCl(S2CNMe2)

Synthesis, magnetic and spectral studies of some new mixed-ligand nitrosyl complexes of chromium(I)

Synthesis and characterization of epoxy resin in the presence of p-acetylbenylidene triphenylarsoniumylide-mercuric chloride complex

Synthesis and characterization of chlorodibenzyltin(IV) complexes with N,N-dialkyl dithiocarbamate ligands and crystal structure of (PhCH₂)₂SnCl(S₂CNMe₂)