Evaluation of the Giant Ferromagnetic π–d Interaction in Iron-Phthalocyanine Molecule

Sánchez-de-Armas, Rocío; Calzado, Carmen J.

doi:10.1021/acs.jpca.7b11356

Cited by 7 publications

(7 citation statements)

References 82 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In Cl-(MnPc) 2 the moment stays at 3.74 μ B on Mn1, and it is lowered to −0.11 in the ring. The antiferromagnetic coupling observed in all these cases between the central metal and the organic ring was also been observed for several metal Pc’s deposited on surfaces, , while for some Pc-based 3D materials, it was found to be ferromagnetic, for example, in FePc (CN) 2 ·2CHCl 3 crystals …”

Section: Resultssupporting

confidence: 59%

Chemical Switching of the Magnetic Coupling in a MnPc Dimer by Means of Chemisorption and Axial Ligands

2020

View full text Add to dashboard Cite

We present an ab initio density functional theory study of the magnetic properties of manganese phthalocyanine dimers, where we focus on the magnetic coupling between the Mn centers and on how it is affected by external factors like chemisorption or atomic axial ligands. We have studied several different configurations for the gas phase dimers, which resulted in ferromagnetic couplings of different magnitudes. For the bare dimer we find a significant ferromagnetic coupling between the Mn centers, which decreases by about 20% when a H atom is adsorbed on one of the Mn atoms and is reduced to about 7% when a Cl atom is adsorbed. The magnetic coupling is almost fully quenched when the dimer, bare or with the H ligand, is deposited on the ferromagnetic substrate Co(001). Our calculations indicate that the coupling between the two Mn atoms principally occurs via a superexchange interaction along two possible paths within a Mn–N–Mn–N four-atom loop. When these electrons get involved in chemical bonding outside the dimer itself, an appreciable alteration of the overlap between Mn and N molecular orbitals along the loop occurs, and consequently, the magnetic interaction between the Mn centers varies. We show that this is reflected by the electronic structure of the dimer in various configurations and is also visible in the structure of the atomic loop. The chemical tuning of the magnetic coupling is highly relevant for the design of nanodevices like molecular spin valves, where the molecules need to be anchored to a support.

show abstract

Section: Resultssupporting

confidence: 59%

Chemical Switching of the Magnetic Coupling in a MnPc Dimer by Means of Chemisorption and Axial Ligands

2020

View full text Add to dashboard Cite

show abstract

“…The effect of altering the structure of coumarins on its dye sensitizer properties has been studied by number of researchers. [70][71][72][73][74][75] Sanchez et.al. [70] have carried out exhaustive study about the effect of the substitutions, involving multiple substitution positions, on the absorbance behaviour and energy levels of the coumarins.…”

Section: Introductionmentioning

confidence: 99%

“…[70][71][72][73][74][75] Sanchez et.al. [70] have carried out exhaustive study about the effect of the substitutions, involving multiple substitution positions, on the absorbance behaviour and energy levels of the coumarins. The present work involves substitution at single position however, it gives a detailed account of such substitution on the dye -I 2 interaction and hence, back electron recombinations along with other optical as well as photovoltaic parameters.…”

Section: Introductionmentioning

confidence: 99%

Theoretical Studies on the Structure, Optoelectronic and Photosensitizer Applications of NKX Class of Coumarin Dye Molecules

Manzoor

Pandith

2018

ChemistrySelect

View full text Add to dashboard Cite

Coumarin based NKX class of molecules have been recently investigated for their promising sensitizing applications in dye Sensitized Solar Cells (DSSCs). However, the various factors limiting the sensitizing properties of these molecules such as charge transport efficiency and electron back recombination still remain to be understood properly. Herein, we report a detailed theoretical study on the structural, opto‐electronic and photo‐sensitizer applications of 2‐cyano‐3‐[5‐(1, 1, 6,6‐tetramethyl‐10‐oxo‐2,3,5,6‐tetrahydro‐1H,4H,10H‐11‐oxa‐3a‐aza‐benzo[de]anthracen‐9‐yl)‐thiophen‐2‐yl]‐acrylicacid (NKX 2587) based dye molecules. Structural variation of the dye molecule through derivatization has been attempted, with the main emphasis on the minimization of the back electron recombination rates through reduced dye – I2 interaction. The optical and photovoltaic properties of these dyes were studied in terms of the key parameters like, HOMO‐LUMO energy gap, maximum absorption wavelength, λmax, light harvesting efficiency, charge injection efficiency, open voltage, reorganization energy etc. using density functional theory methods. The results reflect that the dyes with more electron withdrawing substituents exhibit lower dye – I2 interaction, thus minimizing the back recombination. Moreover, the dyes with chloro (C3), bromo (C4), iodo (C5) and cyano (C7) substituents exhibit almost double electronic injection efficiency in comparison to the parent sensitizer molecule and are hence, expected to enhance the efficiency of the DSSCs based on such systems.

show abstract

“…The theoretical studies have served as a tool for verifying the results found experimentally. As such, number of such studies has been carried out, such as those based on coumarins [10][11][12][13][14][15][16] and triphenylamine. [17][18][19][20] Theoretical studies by several researchers [15,[21][22][23][24][25] on NKX coumarin derivatives have been carried for understanding the relationship between the molecular properties of these dye sensitizers and the energy conversion efficiency of DSSCs.Theoretical calculation, particularly DFT methods have evolved as very effective and useful tools for optimizing a system for achieving better results for efficient DSSCs.…”

mentioning

confidence: 99%

“…Researchers have worked on the different type of coumarins usually NKX-based ones, as donors for DSSC applications. [10][11][12][13][14][15][16] But, the basic coumarin molecules like bicoumarin, coumarin, dihydrofurano coumarin, furano coumarin, phenyl coumarin, pyranoanglar coumarin, and pyranolinear coumarin, have been hardly studied in this perspective. [49][50][51] In this regard, we have made an attempt to use these coumarin molecules as donors for the push-pull systems.…”

mentioning

confidence: 99%

Exploring the effect of different coumarin donors on the optical and photovoltaic properties of azo‐bridged push‐pull systems: A theoretical approach

Manzoor

Niaz

Pandith

2019

Int J of Quantum Chemistry

View full text Add to dashboard Cite

We report the theoretical modeling of various azo-bridged coumarin-purpurin systems. The effect of varying the donor (coumarin) part of this D-π-D-π-A system was analyzed in terms of opto-electronic and photovoltaic parameters such as HOMO, LUMO, HOMO-LUMO energy gap, λ max , light harvesting efficiency, charge injection efficiency, open voltage, reorganization energy by employing density functional theory as incorporated in Gaussian 03 set of codes. The dye-TiO 2 adsorbed systems were also studied using the same level of theory. It was found that just by varying the donor, although of same nature, there is a marked effect on the efficiency parameters of the dye sensitized solar cells based on such dyes. Also, the dye molecules were found to be good sensitizers for TiO 2 semiconductors. K E Y W O R D S DFT, DSSC, light harvesting efficiency, optoelectronic, photovoltaic parameters | INTRODUCTIONDue to the over exploitation of the natural resources coupled with the increasing levels of pollutions, there is immediate need to develop some alternative, clean resources of energy. In this regard, solar energy is the easily available and clean form of energy that can be well harnessed to meet our present as well as future energy demands. To convert this solar energy into usable forms we have some devices called photovoltaic solar devices and amongst them dye sensitized solar cells (DSSC) are better options, owing to their easy manufacture, cost effectiveness, and flexibility.With the advent of the DSSC technology the conversion of the solar energy to electricity became cheap than the traditional silicon-based photovoltaics. [1,2] Amongst DSSCs, those based on organic dye sensitizers have been found to be advantageous owing to their easy synthesis and low cost. The study of these organic metal free dye sensitizers for DSSCs are important as they have paved the way for designing DSSCs with better efficiencies in a cost effective manner. Organic dyes have exhibited higher conversion efficiencies up to 12.5% for carbazoles and indenoperylene electron-donor based dye sensitizers while as 12.8% efficiency has been achieved for triphenylamine-based dye using cobalt-based electrolyte system. [3,4] Amongst the organic sensitizers, those based on push-pull framework or donor-π-acceptor (D-π-A) form are worth mentioning These push-pull dye molecules are very promising due to their high molar extinction coefficient, cost effectiveness, and diversity. [5][6][7][8][9] Along with experimental studies, a number of theoretical researches have been carried out on various organic dyes. The theoretical studies have served as a tool for verifying the results found experimentally. As such, number of such studies has been carried out, such as those based on coumarins [10][11][12][13][14][15][16] and triphenylamine. [17][18][19][20] Theoretical studies by several researchers [15,[21][22][23][24][25] on NKX coumarin derivatives have been carried for understanding the relationship between the molecular properties of these dye sensitizers and the...

show abstract

Evaluation of the Giant Ferromagnetic π–d Interaction in Iron-Phthalocyanine Molecule

Cited by 7 publications

References 82 publications

Chemical Switching of the Magnetic Coupling in a MnPc Dimer by Means of Chemisorption and Axial Ligands

Chemical Switching of the Magnetic Coupling in a MnPc Dimer by Means of Chemisorption and Axial Ligands

Theoretical Studies on the Structure, Optoelectronic and Photosensitizer Applications of NKX Class of Coumarin Dye Molecules

Exploring the effect of different coumarin donors on the optical and photovoltaic properties of azo‐bridged push‐pull systems: A theoretical approach

Contact Info

Product

Resources

About