Thio derivatives of b-diketones and their metal chelates. IV. Adducts of nickel(II) chelates of Monothio-β-diketones with aromatic heterocyclicbases

1966 ◽  
Vol 19 (8) ◽  
pp. 1401 ◽  
Author(s):  
SHH Chaston ◽  
SE Livingstone ◽  
TN Lockyer
Keyword(s):  
Absorption Spectra ◽  
Reflectance Spectra ◽  
Spectral Measurements ◽  
Octahedral Structure ◽  
Visible Absorption ◽  
Diethyl Dithiocarbamate ◽  
Visible Reflectance ◽  
Derivatives Of ◽  
Diethyl Dithiophosphate ◽  
Spectrochemical Series

Paramagnetic adducts of nickel(II) chelates of monothio-β-diketones have been obtained with pyridine, γ-picoline, 1,l0-phenanthroline, 2-methyl-1,10-phenanthroline, 2,2'-bipyridyl, and 2,2',2"-terpyridyl. Their paramagnetism and visible reflectance spectra are consistent with octahedral nickel(II). The pyridine and γ-picoline adducts probably have a trans octahedral structure, while there are three possible octahedral configurations for the adducts of the phenanthrolines and bipyridyl. The terpyridyl adduct of Ni(NeCS=CHCOOMe)2 was obtained in two forms but the data obtained from infrared and visible absorption spectral measurements are insufficient to establish which of the several possible structures occur. The characteristic infrared bands of the adducts are given. The visible absorption spectra of the diamagnetic nickel(II) chelates of the monothio-β-diketones indicate that these ligands lie between diethyl dithiophosphate and diethyl dithiocarbamate in the spectrochemical series.

CO-ORDINATION COMPOUNDS OF NICKEL(II): PART I. THE SPECTRA OF SALICYLALDIMINE DERIVATIVES OF NICKEL(II) IN SOME ORGANIC SOLVENTS

1959 ◽  
Vol 37 (2) ◽  
pp. 436-443 ◽  
Author(s):  
H. C. Clark ◽  
R. J. O'Brien
Keyword(s):  
Field Theory ◽  
Carbon Tetrachloride ◽  
Absorption Spectra ◽  
Organic Solvents ◽  
Ligand Field ◽  
Temperature Dependent ◽  
Visible Absorption ◽  
Ligand Field Theory ◽  
Recent Developments ◽  
Derivatives Of

Measurements of the ultraviolet and visible absorption spectra of bis-N-methyl-salicylaldimine nickel(II) and its 5-chloro and 5-bromo derivatives in benzene, chloroform, carbon tetrachloride, and cyclohexane solutions at temperatures between 15° and 45 °C are reported. The results confirm the occurrence of a temperature dependent equilibrium between dia- and para-magnetic forms. The nature of the paramagnetic form is discussed in terms of the recent developments of the ligand field theory. The effect on the equilibrium of substitution of chlorine or bromine in the five position of the salicylaldehyde molecule is also discussed.

Influence of Electron Injection Rate in Triphenylamine Based Dye for Dye-Sensitized Solar Cells: A First Principle Study

2019 ◽  
Vol 233 (9) ◽  
pp. 1247-1259
Author(s):  
Madhu Prakasam
Keyword(s):  
Solar Cells ◽  
Absorption Spectra ◽  
Density Functional ◽  
Dye Sensitized Solar Cells ◽  
Visible Region ◽  
Electron Injection ◽  
Injection Rate ◽  
Visible Absorption ◽  
Dye Sensitized ◽  
Sensitized Solar Cells

Abstract In this work, we systematically investigate the impacts of electron-donor based on Triphenylamine (TPA). The Geometry structure, energy levels, light-harvesting ability and ultraviolet-visible absorption spectra were calculated by using Density Functional Theory (DFT) and Time-Dependent-DFT. The electron injection rate of the TPA-N(CH3)2 based dyes has 0.71 eV for high among the dye sensitizer. The First and Second order Hyperpolarizability of the 11.95 × 10−30 e.s.u and 12195.54 a.u, respectively for TPA-N(CH3)2 based dye. The calculated absorption spectra were showed in the ultra-violet visible region for power conversion region. The study reveals that the electron transfer character of TPA-N(CH3)2 based dyes can be made suitable for applications in Dye-Sensitized Solar Cells.

scholarly journals The Importance of Motions that Accompany Those Occurring Along the Reaction Coordinate

2015 ◽  
Vol 68 (8) ◽  
pp. 1202 ◽  
Author(s):  
Jeffrey R. Reimers
Keyword(s):  
Reaction Coordinate ◽  
Spectral Measurements ◽  
Visible Absorption ◽  
Photochemical Process ◽  
New Approach ◽  
Energy Devices ◽  
Adiabatic Theory ◽  
Core Theory ◽  
Basic Ideas

The reaction coordinate is a well known quantity used to define the motions critical to chemical reactions, but many other motions always accompany it. These other motions are typically ignored but this is not always possible. Sometimes it is not even clear as to which motions comprise the reaction coordinate: spectral measurements that one may assume are dominated by the reaction coordinate could instead be dominated by the accompanying modes. Examples of different scenarios are considered. The assignment of the visible absorption spectrum of chlorophyll-a was debated for 50 years, with profound consequences for the understanding of how light energy is transported and harvested in natural and artificial solar-energy devices. We recently introduced a new, comprehensive, assignment, the centrepiece of which was determination of the reaction coordinate for an unrecognized photochemical process. The notion that spectroscopy and reactivity are so closely connected comes directly from Hush’s adiabatic theory of electron-transfer reactions. Its basic ideas are reviewed, similarities to traditional chemical theories drawn, key analytical results described, and the importance of the accompanying modes stressed. Also highlighted are recent advances that allow this theory to be applied to general transformations including isomerization processes, hybridization, aromaticity, hydrogen bonding, and understanding why the properties of first-row molecules such as NH3 (bond angle 108°) are so different to those of PH3–BiH3 (bond angles 90–93°). Historically, the question of what is the reaction coordinate and what is just an accompanying motion has not commonly been at the forefront of attention. In our new approach in which all chemical processes are described using the same core theory, this question becomes thrust forward as always being the most important qualitative feature to determine.

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