Spectroscopic investigation and characterization of polypyrrole film doped with [MeN4]2[Ni(dmit)2] complex salt

Molecular organization and doping in poly(2-methoxyaniline)/Ni(dmit)2 films obtained with the Langmuir–Blodgett technique

“…11 The [Ni(dmit) 2 ](CTAB) 2 LB film spectrum shows bands at 320, 355, 410 and 462 nm due to the intraligand p-p* transition, and at 640 nm due to the metal-ligand charge transfer transition (MLCT). 31 All bands are redshifted in comparison to the spectra in solution and two more bands are present due to the existence of intermolecular interactions in the solid state as already observed in [Ni(dmit) 2 ] 22 LB films. 36,37 The tail above 1000 nm for the [Ni(dmit) 2 ](CTAB) 2 LB film can be compared to the band at 1150 which is assigned to electronic transitions within the [Ni(dmit)] 22 moieties in similar systems.…”

“…The broad band between 410 and 460 nm in the Langmuir film corresponds to that centered at 400 nm for the solution spectrum, which is assigned to the p(Sm)-p*(CLS) transition. 31 The other part of the spectra that slightly increases in intensity with film compression (above 600 nm) is difficult to analyze. It is probable that the band around 560 nm in the solution spectrum (assigned to metal-ligand charge transfer transitions 31 ) is superimposed with weak, broad bands for [Ni(dmit) 2 ](CTAB) 2 around 650 and 770 nm due to p(Sm)-p*(CLS) or metal-ligand charge transfer transitions, respectively.…”

“…31 The other part of the spectra that slightly increases in intensity with film compression (above 600 nm) is difficult to analyze. It is probable that the band around 560 nm in the solution spectrum (assigned to metal-ligand charge transfer transitions 31 ) is superimposed with weak, broad bands for [Ni(dmit) 2 ](CTAB) 2 around 650 and 770 nm due to p(Sm)-p*(CLS) or metal-ligand charge transfer transitions, respectively. 31 This difficulty arises because the in situ UV-Vis spectra for Langmuir films normally have a less defined shape, with band shifts caused by aggregation.…”

“…It is probable that the band around 560 nm in the solution spectrum (assigned to metal-ligand charge transfer transitions 31 ) is superimposed with weak, broad bands for [Ni(dmit) 2 ](CTAB) 2 around 650 and 770 nm due to p(Sm)-p*(CLS) or metal-ligand charge transfer transitions, respectively. 31 This difficulty arises because the in situ UV-Vis spectra for Langmuir films normally have a less defined shape, with band shifts caused by aggregation. 21 For the hybrid POMA/[Ni(dmit) 2 ](CTAB) 2 Langmuir film, small absorptions at shorter wavelengths (,450 nm) are observed in Fig.…”

Vibrational and Electronic Spectroscopy of Neutral Antimony Coordination Compounds of the 1,3-Dithiole-2-thione-4,5-dithiolate (dmit)

“…Solomon and co-workers have been using sulfur K-shell (1s) photoabsorption spectroscopy to study the covalent character of transition metal–thiolate bonds, in both anionic chelates and bridging sulfides, which are models for biological systems. − The assignments have been established using DFT calculations. X-ray photoelectron spectroscopy (XPS) and X-ray absorption near edge structure (XANES) spectroscopy, using synchrotron radiation, have also been used to study thiols chemisorbed on metallic surfaces. − Finally, polypyrrole systems, doped with [NEt 4 ] 2 [Ni­(dmit) 2 ], have been studied recently using inner-shell photofragmentation techniques at the S 1s edge. , …”