Heavy ligand atom induced large magnetic anisotropy in Mn(<scp>ii</scp>) complexes

Chowdhury, Sabyasachi Roy; Mishra, Sabyashachi

doi:10.1039/c7cp02957h

“…The value reduces to a relatively smaller magnitude, <−3 cm –1 , for the HS state on the geometry optimized in the HS state. An exception is observed for complexes 4 and 12 , where a notable spin–orbit coupling is coming from heavy iodide ligand . The large SOC in these complexes lowers the energy of quartet excited state and brings it closer to the sextet ground state and provides D values of −9.78 and −18.02 cm –1 , respectively.…”

Section: Resultsmentioning

confidence: 95%

“…An exception is observed for complexes 4 and 12, where a notable spin−orbit coupling is coming from heavy iodide ligand. 85 The large SOC in these complexes lowers the energy of quartet excited state and brings it closer to the sextet ground state and provides D values of −9.78 and −18.02 cm −1 , respectively. However, for other complexes that are stabilized in HS state, a very small amount of zero field splitting, <−4 cm −1 , is observed in both the spin states on their respective geometries.…”

Section: The Journal Of Physicalmentioning

confidence: 99%

First-Principles Investigations of Magnetic Anisotropy and Spin-Crossover Behavior of Fe(III)–TBP Complexes

Khurana¹,

Gupta²,

Ali³

2021

View full text Add to dashboard Cite

With the ongoing effort to obtain mononuclear 3d-transitionmetal complexes that manifest slow relaxation of magnetization and, hence, can behave as single-molecule magnets (SMMs), we have modeled 14 Fe(III) complexes based on an experimentally synthesized (PMe 3 ) 2 FeCl 3 complex [J. Am. Chem. Soc. 2017, 139 (46), 16474−16477], by varying the axial ligands with group XV elements (N, P, and As) and equatorial halide ligands from F, Cl, Br, and I. Out of these, nine complexes possess large zero field splitting (ZFS) parameter D in the range of −40 to −60 cm −1 . The first-principles investigation of the ground-spin state applying density functional theory (DFT) and wave function-based multiconfigurations methods, e.g., SA-CASSCF/NEVPT2, are found to be quite consistent except for few delicate cases with near-degenerate spin states. In such cases, the hybrid B3LYP functional is found to be biased toward high-spin (HS) state. Altering the percentage of exact exchange admixed in the B3LYP functional leads to intermediate-spin (IS) ground state consistent with the multireference calculations. The origin of large zero field splitting (ZFS) in the Fe(III)-based trigonal bipyramidal (TBP) complexes is investigated. Furthermore, a number of complexes are identified with very small ΔG HS−IS adia. values indicating the possible spin-crossover phenomenon between the bistable spin states.

show abstract

“…An exception is observed for complex 4 and 12 where a notable spin-orbit coupling is coming from heavy iodide ligand. 79 The large SOC in these complexes lowers the energy of quartet excited state and brings it closer to the sextet ground state and gives a D value of -9.78 and -18.02 cm −1 respectively. However, for other complexes which are stabilized in HS state, very small amount of zero field splitting, < -4 cm −1 , is observed in both the spin-states on their respective geometries.…”

Section: Zero Field Splittingmentioning

confidence: 99%

First-Principles Investigations of Magnetic Anisotropy and Spin-Crossover Behavior of Fe(III)-TBP Complexes

Khurana¹,

Gupta²,

Ali³

2020

Preprint

0

View full text Add to dashboard Cite

<div>With the ongoing efforts to obtain mononuclear 3d-transition metal complexes that manifest slow relaxation of magnetization and hence, can behave as single molecule magnets (SMMs), we have modelled 14 novel Fe(III) complexes out of which nine behave as potential SMMs. These complexes possess large zero-field splitting (ZFS)</div><div>parameter D in the range of -40 to -60 cm<sup>-1</sup>. The first-principles investigation of the ground-spin state applying density functional theory (DFT) and wave-function based</div><div>multi-configurations methods e.g. SA-CASSCF/NEVPT2 are found to be quite consistent except for few delicate cases with near degenerate spin-states. In such cases, the</div><div>hybrid B3LYP functional is found to be biased towards high-spin (HS) state. Altering the percentage of exact exchange admixed in B3LYP functional leads to intermediate spin</div><div>(IS) ground state consistent with the multireference calculations. The origin of large zero field splitting (ZFS) in the Fe(III)-based trigonal bipyramidal (TBP) complexes</div><div>is investigated and the D-values are further tuned by varying the axial ligands with group XV elements (N, P and As) and equatorial halide ligands from F, Cl, Br and I. Furthermore, a number of complexes are identified with very small Gibbs free energy values indicating the possible spin-crossover phenomenon between the bi-stable spin-states.</div>

show abstract

“…< -3 cm −1 for the HS state on the geometry optimized in HS state. An exception is observed for complex 4 and 12 where a notable spin-orbit coupling is coming from heavy iodide ligand 79. The large SOC in these complexes lowers the energy of quartet excited state and brings it closer to the sextet ground state and gives a D value of -9.78 and -18.02 cm −1 respectively.…”

mentioning

confidence: 93%

First-Principles Investigations of Magnetic Anisotropy and Spin-Crossover Behavior of Fe(III)-TBP Complexes

Khurana¹,

Gupta²,

Ali³

2020

Preprint

View full text Add to dashboard Cite

<div>With the ongoing efforts to obtain mononuclear 3d-transition metal complexes that manifest slow relaxation of magnetization and hence, can behave as single molecule magnets (SMMs), we have modelled 14 novel Fe(III) complexes out of which nine behave as potential SMMs. These complexes possess large zero-field splitting (ZFS)</div><div>parameter D in the range of -40 to -60 cm<sup>-1</sup>. The first-principles investigation of the ground-spin state applying density functional theory (DFT) and wave-function based</div><div>multi-configurations methods e.g. SA-CASSCF/NEVPT2 are found to be quite consistent except for few delicate cases with near degenerate spin-states. In such cases, the</div><div>hybrid B3LYP functional is found to be biased towards high-spin (HS) state. Altering the percentage of exact exchange admixed in B3LYP functional leads to intermediate spin</div><div>(IS) ground state consistent with the multireference calculations. The origin of large zero field splitting (ZFS) in the Fe(III)-based trigonal bipyramidal (TBP) complexes</div><div>is investigated and the D-values are further tuned by varying the axial ligands with group XV elements (N, P and As) and equatorial halide ligands from F, Cl, Br and I. Furthermore, a number of complexes are identified with very small Gibbs free energy values indicating the possible spin-crossover phenomenon between the bi-stable spin-states.</div>

show abstract

Heavy ligand atom induced large magnetic anisotropy in Mn(ii) complexes

Cited by 17 publications

References 53 publications

First-Principles Investigations of Magnetic Anisotropy and Spin-Crossover Behavior of Fe(III)–TBP Complexes

First-Principles Investigations of Magnetic Anisotropy and Spin-Crossover Behavior of Fe(III)–TBP Complexes

First-Principles Investigations of Magnetic Anisotropy and Spin-Crossover Behavior of Fe(III)-TBP Complexes

First-Principles Investigations of Magnetic Anisotropy and Spin-Crossover Behavior of Fe(III)-TBP Complexes

Contact Info

Product

Resources

About