Three Co(II) coordination polymers constructed using 2,2'-oxybis(benzoic acid) and auxiliary N-donor ligands: Syntheses, structures, magnetic behavior and density functional theory studies

2018 ◽  
Vol 8 (5) ◽  
pp. 417-426
Author(s):  
Long Tang ◽  
Ran Jing ◽  
XiangYang Hou ◽  
Xiao Wang ◽  
Ping Ju ◽  
...  
Crystals ◽  
2020 ◽  
Vol 10 (5) ◽  
pp. 391
Author(s):  
Jeannette Carolina Belmont-Sánchez ◽  
María Eugenia García-Rubiño ◽  
Antonio Frontera ◽  
Antonio Matilla-Hernández ◽  
Alfonso Castiñeiras ◽  
...  

Three mixed-ligands of Cd(II) coordination polymers were unintentionally obtained: {[Cd(µ3-EDTA)(Him)·Cd(Him)(H2O)2]·H2O}n (1), {[Cd(µ4-CDTA)(Hade)·Cd(Hade)2]}n (2), and {[Cd(µ3-EDTA)(H2O)·Cd(H9heade)(H2O)]·2H2O}n (3), having imidazole (Him), adenine (Hade) or 9-(2-hydroxyethyl)adenine (9heade) as the N-heterocyclic coligands. Compounds 2 and 3 were obtained by working with an excess of corresponding N-heterocyclic coligands. The single-crystal X-ray diffraction structures and thermogravimetric analyses are reported. The chelate moieties in all three compounds exhibit hepta-coordinated Cd centers, whereas the non-chelated Cd center is five-coordinated in 1 and six-coordinated in 2 and 3. Him and Hade take part in the seven-coordinated chelate moieties in 1 and 2, respectively. In contrast, 9heade is unable to replace the aqua ligand of the chelate [Cd (EDTA) (H2O)] moiety in 3. The thermogravimetric analysis (TGA) behavior of [Cd (H2EDTA) (H2O)]·2H2O in 1 and 3 leads to a residue of CdO, whereas the N-rich compound 2 yields CdO·Cd(NO3)2 as a residue. Density functional theory (DFT) calculations along with molecular electrostatic potential (MEP) and quantum theory of atoms-in-molecules computations were performed in adenine (compound 2) and (2-hydroxyethyl)adenine (compound 3) to analyze how the strength of the H-bonding and π-stacking interactions, respectively, are affected by their coordination to the Cd-metal center.


2018 ◽  
Vol 448 ◽  
pp. 186-191 ◽  
Author(s):  
Narayan N. Som ◽  
Venu H. Mankad ◽  
Shweta D. Dabhi ◽  
Anjali Patel ◽  
Prafulla K. Jha

2015 ◽  
Vol 2015 ◽  
pp. 1-9 ◽  
Author(s):  
Yuehua Zhang ◽  
Penghui Ren ◽  
Yuanzuo Li ◽  
Runzhou Su ◽  
Meiyu Zhao

Density functional theory (DFT) and time-dependent density functional theory (TDDFT) calculations were carried out to study the ground state geometries, electronic structures, and absorption spectra of 4-(cyanomethyl)benzoic acid based dyes (AG1 and AG2) used for dye-sensitized solar cells (DSSCs). The excited states properties and the thermodynamical parameters of electron injection were studied. The results showed that (a) two dyes have uncoplanar structures along the donor unit and conjugated bridge space, (b) two sensitizers exhibited intense absorption in the UV-Vis region, and (c) the excited state oxidation potential was higher than the conduction band edge of TiO2photoanode. As a result, a solar cell based on the 4-(cyanomethyl)benzoic acid based dyes exhibited well photovoltaic performance. Furthermore, nine dyes were designed on the basis of AG1 and AG2 to improve optical response and electron injection.


2006 ◽  
Vol 320 ◽  
pp. 175-178 ◽  
Author(s):  
Kaori Nishizawa ◽  
Haruhiko Fukaya ◽  
Takeshi Miki ◽  
Kazuyuki Suzuki ◽  
Kazumi Kato

A new photochromic ZrO2 precursor solution was prepared using zirconium tetra-n-butoxide, 4-(phenylazo)benzoic acid and ethyleneglycol monomethylether. The ZrO2 precursor solution was irradiated with ultraviolet light (UV) at room temperature. After that, UV-irradiated precursor solution was irradiated with visible light (Vis) at room temperature. UV-Vis spectra were measured before irradiation, after UV irradiation and Vis irradiation. Changes of UV-Vis spectra indicated that the new ZrO2 precursor including 4-(phenylazo)benzoic acid shows photochromism. The phenomena have synchronized with reversible photoisomerization of 4-(phenylazo)benzoic acid in the precursor. In addition, the difference of peak position originated from Zr-O CT transition between before UV irradiation and after UV irradiation increased with increasing the concentration of 4-(phenylazo)benzoic acid. Furthermore, the optimized structure of the new ZrO2 precursor was derived by density functional theory (DFT) calculation.


Sign in / Sign up

Export Citation Format

Share Document