Saeid Jalali Asadabadi | University of Isfahan (original) (raw)

Papers by Saeid Jalali Asadabadi

Physical Chemistry Chemical Physics

The rare-earth or 3d transition metal dopants in perovskites have potential to induce interesting... more The rare-earth or 3d transition metal dopants in perovskites have potential to induce interesting features, thus opening opportunities for investigations and applications.

The Journal of Physical Chemistry C, 2018

Nuclear magnetic resonance (NMR) parameters are calculated and analyzed in a series of titanate o... more Nuclear magnetic resonance (NMR) parameters are calculated and analyzed in a series of titanate of alkaline earth perovskites to explore microscopic sources of their magnetic shieldings using a full-potential-based NMR scheme. In this method, there is no approximation to calculate the induced current density. The slope of the correlation between various approaches and available experimental data is successfully reproduced very close to the required ideal value (−1). Our NMR results are consistent with the experimental data and the available theoretical results calculated by the gauge-including projector augmented-wave (GIPAW) method. Moreover, we have predicted the chemical shifts of the compounds in which their experimental values have not been measured yet. Isotropic and anisotropic chemical shift parameters as well as associated asymmetries are analyzed. The analysis explores the relation between atomic and orbital characters of the valence and conduction bands wave functions as well as the 17O NMR shi...

The Journal of Physical Chemistry C, 2017

The electronic, magnetic and optical properties of Co 2 VAl(111) graphene-like (GL) mono-layer as... more The electronic, magnetic and optical properties of Co 2 VAl(111) graphene-like (GL) mono-layer as well as the (101) and (011) terminations have been calculated based on the density functional theory (DFT) and FP-LAPW+lo method. The GL (111) Co 2 VAl has been grown in (111)crystallographic direction, leading to various and interesting physical properties than those of ther considered directions. The films grown in (101) and (011) directions have shown metallic behavior with low spin-polarization at the Fermi level, while the GL case has shown a perfect half-metallic behavior with an integer amount of magnetic moment (1.00 ߤ) and 0.5 ܸ݁spin flip gap. Thus, it can be a good candidate for spintronic applications. Although all these thin films behave similarly at the UV region, the GL case appears to be different in the infrared (IR) and visible regions. The main plasmonic energies occur in the 12-13.8 eV energy range in the parallel (xx) and perpendicular (zz) directions. Our results show that the incident light cannot propagate in the visible region for all the considered monolayers. electronic, optical and spintronic conditions, it is needed to search the new 2D materials. The GLs of the form MB 2 or MB 4 (M=Al, Mg, Ti, Mo; B=Boron) 13, 14 with high structural stability due to their ionic bonds are good candidates for superconductor applications. Furthermore, based

AIP Advances, 2022

The development of three-dimensional (3D) hybrid organic–inorganic perovskites has sparked much i... more The development of three-dimensional (3D) hybrid organic–inorganic perovskites has sparked much interest because of their rich light-harvesting capabilities in solar cells. However, the understanding of the electronic and optical properties, particularly the excitonic shifts upon structural phase transition with temperature in these materials, is not fully clear. Here, we report the accurate description of electronic and optical properties of mostly studied FAPbI3 across the cubic–tetragonal–hexagonal phases, using the relativistic GW method and Bethe–Salpeter Equation (BSE), including the spin–orbit coupling effects. Our GW calculations reveal that the bandgap values vary from 1.47 to 3.54 eV from the room temperature cubic phase to the low temperature hexagonal phase. Our optical analysis shows that excitonic peaks are blue-shifted, and exciton binding energies estimated by the model BSE approach increase from 74 to 567 meV going from the cubic to hexagonal phases. Our results may...

AIP Advances, 2022

The development of three-dimensional (3D) hybrid organic–inorganic perovskites has sparked much i... more The development of three-dimensional (3D) hybrid organic–inorganic perovskites has sparked much interest because of their rich light-harvesting capabilities in solar cells. However, the understanding of the electronic and optical properties, particularly the excitonic shifts upon structural phase transition with temperature in these materials, is not fully clear. Here, we report the accurate description of electronic and optical properties of mostly studied FAPbI3 across the cubic–tetragonal–hexagonal phases, using the relativistic GW method and Bethe–Salpeter Equation (BSE), including the spin–orbit coupling effects. Our GW calculations reveal that the bandgap values vary from 1.47 to 3.54 eV from the room temperature cubic phase to the low temperature hexagonal phase. Our optical analysis shows that excitonic peaks are blue-shifted, and exciton binding energies estimated by the model BSE approach increase from 74 to 567 meV going from the cubic to hexagonal phases. Our results may...

Physical Chemistry Chemical Physics, 2020

The quasiparticle and excitonic properties of mixed FAPb(I1−xBrx)3 0 ≤ x ≤ 1 alloys are studied. ... more The quasiparticle and excitonic properties of mixed FAPb(I1−xBrx)3 0 ≤ x ≤ 1 alloys are studied. We show that Br-doping provides an efficient and controllable way to tune the band gap and optical properties, beneficial for material design of high performance tandem solar cells.

Physical Chemistry Chemical Physics, 2020

The quasiparticle and excitonic properties of mixed FAPb(I1−xBrx)3 0 ≤ x ≤ 1 alloys are studied. ... more The quasiparticle and excitonic properties of mixed FAPb(I1−xBrx)3 0 ≤ x ≤ 1 alloys are studied. We show that Br-doping provides an efficient and controllable way to tune the band gap and optical properties, beneficial for material design of high performance tandem solar cells.

Journal of Electronic Materials, 2017

Cubic uranium compounds such as UX 3 (X is a non-transition element of groups IIIA or IVA) exhibi... more Cubic uranium compounds such as UX 3 (X is a non-transition element of groups IIIA or IVA) exhibit highly diverse magnetic properties, including Pauli paramagnetism, spin fluctuation and anti-ferromagnetism. In the present paper, we explore the structural, electronic and magnetic properties as well as the hyperfine fields (HFFs) and electric field gradients (EFGs) with quadrupole coupling constant of UX 3 (X = In, Tl, Pb) compounds using local density approximation, Perdew-Burke-Ernzerhof parametrization of generalized gradient approximation (PBE-GGA) including the Hubbard U parameter (GGA + U), a revised version of PBE-GGA that improves equilibrium properties of densely packed solids and their surfaces (PBEsol-GGA), and a hybrid functional (HF-PBEsol). The spin orbit-coupling calculations have been added to investigate the relativistic effect of electrons in these materials. The comparison between the experimental parameters and our calculated structural parameters we confirm the consistency and effectiveness of our theoretical tools. The computed magnetic moments show that magnetic moment increases from indium to lead in the UX 3 family, and all these compounds are antiferromagnetic in nature. The EFGs and HFFs, as well as the quadrupole coupling constant of UX 3 (X = In, Tl, Pb), are discussed in detail. These properties primarily originate from f and p states of uranium and post-transition sites.

Journal of Electronic Materials, 2017

Physics Letters A, 2017

This is a PDF file of an unedited manuscript that has been accepted for publication. As a service... more This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. Highlights • The type of band gap is interestingly affected by bond formation mechanism such as the different energy values of bonding orbitals in different compounds and the weak interaction between p z orbitals of adjacent atoms. • It is concluded that the band gap nature of CdSe, CdTe, ZnSe and ZnTe transforms from direct to indirect. • The optically active nature of all compounds in bulk phase changes into optically inactive nature in monolayer phase apart from CdS and ZnS.

Bulletin of Materials Science, 2016

Bulletin of Materials Science, 2016

Journal of Electronic Materials, 2015

The electronic properties of pristine fcc-C60 are calculated by utilizing a variety of density fu... more The electronic properties of pristine fcc-C60 are calculated by utilizing a variety of density functional theory (DFT) approaches including the Perdew-Burke-Ernzerhof generalized gradient approximation (PBE-GGA), PBE-GGA+DFT-D3(vdW), Engel and Vosko GGA (EV-GGA), GGA plus Hubbard U parameter (GGA+U), hybrids Becke–Perdew–Wang hybrid functional (B3PW91), Becke–Lee–Yang–Parr hybrid functional (B3LYP), the PBE exchange-correlation functional (PBE0), and Tran and Blaha regular and non-regular modified Becke and Johnson (TB-mBJ) potential within a DFT frame work using augmented plane waves plus local orbital method. The comparison of the calculated results with the experimental values shows that the non-regular TB-mBJ method reproduces a correct experimental direct band gap of 2.12 eV at X symmetry for this compound. The effectiveness of this theoretical approach in the reproduction of the experimental band gap is due to the proper treatment of the electrons in the interstitial region of the crystal. Our results show that the C60 clusters are weakly interacting with each other in the fcc crystal. This study also reveals that the five-fold degeneracies of the isolated C60 molecule due to its icosahedral symmetry are completely lifted at an X symmetry point by the crystal field.

Journal of Electronic Materials, 2015

The electronic properties of pristine fcc-C60 are calculated by utilizing a variety of density fu... more The electronic properties of pristine fcc-C60 are calculated by utilizing a variety of density functional theory (DFT) approaches including the Perdew-Burke-Ernzerhof generalized gradient approximation (PBE-GGA), PBE-GGA+DFT-D3(vdW), Engel and Vosko GGA (EV-GGA), GGA plus Hubbard U parameter (GGA+U), hybrids Becke–Perdew–Wang hybrid functional (B3PW91), Becke–Lee–Yang–Parr hybrid functional (B3LYP), the PBE exchange-correlation functional (PBE0), and Tran and Blaha regular and non-regular modified Becke and Johnson (TB-mBJ) potential within a DFT frame work using augmented plane waves plus local orbital method. The comparison of the calculated results with the experimental values shows that the non-regular TB-mBJ method reproduces a correct experimental direct band gap of 2.12 eV at X symmetry for this compound. The effectiveness of this theoretical approach in the reproduction of the experimental band gap is due to the proper treatment of the electrons in the interstitial region of the crystal. Our results show that the C60 clusters are weakly interacting with each other in the fcc crystal. This study also reveals that the five-fold degeneracies of the isolated C60 molecule due to its icosahedral symmetry are completely lifted at an X symmetry point by the crystal field.

Journal of Physics and Chemistry of Solids, 2015

ABSTRACT

Journal of Physics and Chemistry of Solids, 2015

ABSTRACT

Electronic Materials Letters, 2015

Electronic Materials Letters, 2015

Physical Chemistry Chemical Physics

The rare-earth or 3d transition metal dopants in perovskites have potential to induce interesting... more The rare-earth or 3d transition metal dopants in perovskites have potential to induce interesting features, thus opening opportunities for investigations and applications.

The Journal of Physical Chemistry C, 2018

Nuclear magnetic resonance (NMR) parameters are calculated and analyzed in a series of titanate o... more Nuclear magnetic resonance (NMR) parameters are calculated and analyzed in a series of titanate of alkaline earth perovskites to explore microscopic sources of their magnetic shieldings using a full-potential-based NMR scheme. In this method, there is no approximation to calculate the induced current density. The slope of the correlation between various approaches and available experimental data is successfully reproduced very close to the required ideal value (−1). Our NMR results are consistent with the experimental data and the available theoretical results calculated by the gauge-including projector augmented-wave (GIPAW) method. Moreover, we have predicted the chemical shifts of the compounds in which their experimental values have not been measured yet. Isotropic and anisotropic chemical shift parameters as well as associated asymmetries are analyzed. The analysis explores the relation between atomic and orbital characters of the valence and conduction bands wave functions as well as the 17O NMR shi...

The Journal of Physical Chemistry C, 2017

The electronic, magnetic and optical properties of Co 2 VAl(111) graphene-like (GL) mono-layer as... more The electronic, magnetic and optical properties of Co 2 VAl(111) graphene-like (GL) mono-layer as well as the (101) and (011) terminations have been calculated based on the density functional theory (DFT) and FP-LAPW+lo method. The GL (111) Co 2 VAl has been grown in (111)crystallographic direction, leading to various and interesting physical properties than those of ther considered directions. The films grown in (101) and (011) directions have shown metallic behavior with low spin-polarization at the Fermi level, while the GL case has shown a perfect half-metallic behavior with an integer amount of magnetic moment (1.00 ߤ) and 0.5 ܸ݁spin flip gap. Thus, it can be a good candidate for spintronic applications. Although all these thin films behave similarly at the UV region, the GL case appears to be different in the infrared (IR) and visible regions. The main plasmonic energies occur in the 12-13.8 eV energy range in the parallel (xx) and perpendicular (zz) directions. Our results show that the incident light cannot propagate in the visible region for all the considered monolayers. electronic, optical and spintronic conditions, it is needed to search the new 2D materials. The GLs of the form MB 2 or MB 4 (M=Al, Mg, Ti, Mo; B=Boron) 13, 14 with high structural stability due to their ionic bonds are good candidates for superconductor applications. Furthermore, based

AIP Advances, 2022

The development of three-dimensional (3D) hybrid organic–inorganic perovskites has sparked much i... more The development of three-dimensional (3D) hybrid organic–inorganic perovskites has sparked much interest because of their rich light-harvesting capabilities in solar cells. However, the understanding of the electronic and optical properties, particularly the excitonic shifts upon structural phase transition with temperature in these materials, is not fully clear. Here, we report the accurate description of electronic and optical properties of mostly studied FAPbI3 across the cubic–tetragonal–hexagonal phases, using the relativistic GW method and Bethe–Salpeter Equation (BSE), including the spin–orbit coupling effects. Our GW calculations reveal that the bandgap values vary from 1.47 to 3.54 eV from the room temperature cubic phase to the low temperature hexagonal phase. Our optical analysis shows that excitonic peaks are blue-shifted, and exciton binding energies estimated by the model BSE approach increase from 74 to 567 meV going from the cubic to hexagonal phases. Our results may...

AIP Advances, 2022

The development of three-dimensional (3D) hybrid organic–inorganic perovskites has sparked much i... more The development of three-dimensional (3D) hybrid organic–inorganic perovskites has sparked much interest because of their rich light-harvesting capabilities in solar cells. However, the understanding of the electronic and optical properties, particularly the excitonic shifts upon structural phase transition with temperature in these materials, is not fully clear. Here, we report the accurate description of electronic and optical properties of mostly studied FAPbI3 across the cubic–tetragonal–hexagonal phases, using the relativistic GW method and Bethe–Salpeter Equation (BSE), including the spin–orbit coupling effects. Our GW calculations reveal that the bandgap values vary from 1.47 to 3.54 eV from the room temperature cubic phase to the low temperature hexagonal phase. Our optical analysis shows that excitonic peaks are blue-shifted, and exciton binding energies estimated by the model BSE approach increase from 74 to 567 meV going from the cubic to hexagonal phases. Our results may...

Physical Chemistry Chemical Physics, 2020

The quasiparticle and excitonic properties of mixed FAPb(I1−xBrx)3 0 ≤ x ≤ 1 alloys are studied. ... more The quasiparticle and excitonic properties of mixed FAPb(I1−xBrx)3 0 ≤ x ≤ 1 alloys are studied. We show that Br-doping provides an efficient and controllable way to tune the band gap and optical properties, beneficial for material design of high performance tandem solar cells.

Physical Chemistry Chemical Physics, 2020

The quasiparticle and excitonic properties of mixed FAPb(I1−xBrx)3 0 ≤ x ≤ 1 alloys are studied. ... more The quasiparticle and excitonic properties of mixed FAPb(I1−xBrx)3 0 ≤ x ≤ 1 alloys are studied. We show that Br-doping provides an efficient and controllable way to tune the band gap and optical properties, beneficial for material design of high performance tandem solar cells.

Journal of Electronic Materials, 2017

Cubic uranium compounds such as UX 3 (X is a non-transition element of groups IIIA or IVA) exhibi... more Cubic uranium compounds such as UX 3 (X is a non-transition element of groups IIIA or IVA) exhibit highly diverse magnetic properties, including Pauli paramagnetism, spin fluctuation and anti-ferromagnetism. In the present paper, we explore the structural, electronic and magnetic properties as well as the hyperfine fields (HFFs) and electric field gradients (EFGs) with quadrupole coupling constant of UX 3 (X = In, Tl, Pb) compounds using local density approximation, Perdew-Burke-Ernzerhof parametrization of generalized gradient approximation (PBE-GGA) including the Hubbard U parameter (GGA + U), a revised version of PBE-GGA that improves equilibrium properties of densely packed solids and their surfaces (PBEsol-GGA), and a hybrid functional (HF-PBEsol). The spin orbit-coupling calculations have been added to investigate the relativistic effect of electrons in these materials. The comparison between the experimental parameters and our calculated structural parameters we confirm the consistency and effectiveness of our theoretical tools. The computed magnetic moments show that magnetic moment increases from indium to lead in the UX 3 family, and all these compounds are antiferromagnetic in nature. The EFGs and HFFs, as well as the quadrupole coupling constant of UX 3 (X = In, Tl, Pb), are discussed in detail. These properties primarily originate from f and p states of uranium and post-transition sites.

Journal of Electronic Materials, 2017

Physics Letters A, 2017

This is a PDF file of an unedited manuscript that has been accepted for publication. As a service... more This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. Highlights • The type of band gap is interestingly affected by bond formation mechanism such as the different energy values of bonding orbitals in different compounds and the weak interaction between p z orbitals of adjacent atoms. • It is concluded that the band gap nature of CdSe, CdTe, ZnSe and ZnTe transforms from direct to indirect. • The optically active nature of all compounds in bulk phase changes into optically inactive nature in monolayer phase apart from CdS and ZnS.

Bulletin of Materials Science, 2016

Bulletin of Materials Science, 2016

Journal of Electronic Materials, 2015

The electronic properties of pristine fcc-C60 are calculated by utilizing a variety of density fu... more The electronic properties of pristine fcc-C60 are calculated by utilizing a variety of density functional theory (DFT) approaches including the Perdew-Burke-Ernzerhof generalized gradient approximation (PBE-GGA), PBE-GGA+DFT-D3(vdW), Engel and Vosko GGA (EV-GGA), GGA plus Hubbard U parameter (GGA+U), hybrids Becke–Perdew–Wang hybrid functional (B3PW91), Becke–Lee–Yang–Parr hybrid functional (B3LYP), the PBE exchange-correlation functional (PBE0), and Tran and Blaha regular and non-regular modified Becke and Johnson (TB-mBJ) potential within a DFT frame work using augmented plane waves plus local orbital method. The comparison of the calculated results with the experimental values shows that the non-regular TB-mBJ method reproduces a correct experimental direct band gap of 2.12 eV at X symmetry for this compound. The effectiveness of this theoretical approach in the reproduction of the experimental band gap is due to the proper treatment of the electrons in the interstitial region of the crystal. Our results show that the C60 clusters are weakly interacting with each other in the fcc crystal. This study also reveals that the five-fold degeneracies of the isolated C60 molecule due to its icosahedral symmetry are completely lifted at an X symmetry point by the crystal field.

Journal of Electronic Materials, 2015

The electronic properties of pristine fcc-C60 are calculated by utilizing a variety of density fu... more The electronic properties of pristine fcc-C60 are calculated by utilizing a variety of density functional theory (DFT) approaches including the Perdew-Burke-Ernzerhof generalized gradient approximation (PBE-GGA), PBE-GGA+DFT-D3(vdW), Engel and Vosko GGA (EV-GGA), GGA plus Hubbard U parameter (GGA+U), hybrids Becke–Perdew–Wang hybrid functional (B3PW91), Becke–Lee–Yang–Parr hybrid functional (B3LYP), the PBE exchange-correlation functional (PBE0), and Tran and Blaha regular and non-regular modified Becke and Johnson (TB-mBJ) potential within a DFT frame work using augmented plane waves plus local orbital method. The comparison of the calculated results with the experimental values shows that the non-regular TB-mBJ method reproduces a correct experimental direct band gap of 2.12 eV at X symmetry for this compound. The effectiveness of this theoretical approach in the reproduction of the experimental band gap is due to the proper treatment of the electrons in the interstitial region of the crystal. Our results show that the C60 clusters are weakly interacting with each other in the fcc crystal. This study also reveals that the five-fold degeneracies of the isolated C60 molecule due to its icosahedral symmetry are completely lifted at an X symmetry point by the crystal field.

Journal of Physics and Chemistry of Solids, 2015

ABSTRACT

Journal of Physics and Chemistry of Solids, 2015

ABSTRACT

Electronic Materials Letters, 2015

Electronic Materials Letters, 2015