Spin states of Mn(II) and Fe(III) complexes with thiosemicarbazone
Abstract
Mn(II) and Fe(III) complexes with condensation product of thiosemicarbazide and 2-acetylthiazole have been synthesized and characterized by single-crystal X-ray diffraction. Two complexes have the same ligand system – bis tridentate coordination of the thiosemicarbazone ligand through the NNS donor set of atoms. Furthermore, the central metal ions in both cases have the same d5
electronic configuration. However, measured magnetism and analysis of the crystal geometries
show that these two complexes have a different number of unpaired electrons. We
rationalized the results by electronic structure calculations based on density functional
theory. High-spin Mn(II) complex has trigonal-prismatic geometry with ionic metal-ligand bonding. Hund's rule of maximum multiplicity is responsible for its sextet spin-ground state. On the other hand, low-spin Fe(III) complex has octahedral coordination and strong metal-ligand covalency with delocalization of spin density toward ligands. Low-spi...n, doublet state is favored because of the nephelauxetic effect, i.e., smaller pairing energy in Fe(III) complex. Our results show that the difference in the electronic structure of the two complexes, i.e., different spin-ground states, directly affects these molecules' structure, magnetism, reactivity, and biological activities.
Keywords:
spin states / metal-ligand bonding / Mn(II) / Fe(III) / transition metal complexes / coordination chemistry / geometries / spin densitySource:
6th EuChemS Inorganic Chemistry Conference, September 3 – 7, 2023, Institute of Applied Synthetic Chemistry, TU Wien, Austria, 2023, PO-133-PO-133Publisher:
- Viena, Austria : Institute of Applied Synthetic Chemistry, TU Wien
- ChemIT e.U.
Funding / projects:
- TMMagCat - Tailoring Molecular Magnets and Catalysts Based on Transition Metal Complexes (RS-ScienceFundRS-Ideje-7750288)
- Ministry of Science, Technological Development and Innovation of the Republic of Serbia, institutional funding - 200026 (University of Belgrade, Institute of Chemistry, Technology and Metallurgy - IChTM) (RS-MESTD-inst-2020-200026)
- Ministry of Science, Technological Development and Innovation of the Republic of Serbia, institutional funding - 200168 (University of Belgrade, Faculty of Chemistry) (RS-MESTD-inst-2020-200168)
- Ministry of Science, Technological Development and Innovation of the Republic of Serbia, institutional funding - 200288 (Innovation Center of the Faculty of Chemistry) (RS-MESTD-inst-2020-200288)
Related info:
- Referenced by
https://cer.ihtm.bg.ac.rs/handle/123456789/6572
Institution/Community
IHTMTY - CONF AU - Savić, Milica AU - Jevtović, Mima AU - Čobeljić, Božidar AU - Gruden, Maja AU - Zlatar, Matija PY - 2023 UR - https://cer.ihtm.bg.ac.rs/handle/123456789/6570 AB - Mn(II) and Fe(III) complexes with condensation product of thiosemicarbazide and 2-acetylthiazole have been synthesized and characterized by single-crystal X-ray diffraction. Two complexes have the same ligand system – bis tridentate coordination of the thiosemicarbazone ligand through the NNS donor set of atoms. Furthermore, the central metal ions in both cases have the same d5 electronic configuration. However, measured magnetism and analysis of the crystal geometries show that these two complexes have a different number of unpaired electrons. We rationalized the results by electronic structure calculations based on density functional theory. High-spin Mn(II) complex has trigonal-prismatic geometry with ionic metal-ligand bonding. Hund's rule of maximum multiplicity is responsible for its sextet spin-ground state. On the other hand, low-spin Fe(III) complex has octahedral coordination and strong metal-ligand covalency with delocalization of spin density toward ligands. Low-spin, doublet state is favored because of the nephelauxetic effect, i.e., smaller pairing energy in Fe(III) complex. Our results show that the difference in the electronic structure of the two complexes, i.e., different spin-ground states, directly affects these molecules' structure, magnetism, reactivity, and biological activities. PB - Viena, Austria : Institute of Applied Synthetic Chemistry, TU Wien PB - ChemIT e.U. C3 - 6th EuChemS Inorganic Chemistry Conference, September 3 – 7, 2023, Institute of Applied Synthetic Chemistry, TU Wien, Austria T1 - Spin states of Mn(II) and Fe(III) complexes with thiosemicarbazone SP - PO-133 EP - PO-133 UR - https://hdl.handle.net/21.15107/rcub_cer_6570 ER -
@conference{ author = "Savić, Milica and Jevtović, Mima and Čobeljić, Božidar and Gruden, Maja and Zlatar, Matija", year = "2023", abstract = "Mn(II) and Fe(III) complexes with condensation product of thiosemicarbazide and 2-acetylthiazole have been synthesized and characterized by single-crystal X-ray diffraction. Two complexes have the same ligand system – bis tridentate coordination of the thiosemicarbazone ligand through the NNS donor set of atoms. Furthermore, the central metal ions in both cases have the same d5 electronic configuration. However, measured magnetism and analysis of the crystal geometries show that these two complexes have a different number of unpaired electrons. We rationalized the results by electronic structure calculations based on density functional theory. High-spin Mn(II) complex has trigonal-prismatic geometry with ionic metal-ligand bonding. Hund's rule of maximum multiplicity is responsible for its sextet spin-ground state. On the other hand, low-spin Fe(III) complex has octahedral coordination and strong metal-ligand covalency with delocalization of spin density toward ligands. Low-spin, doublet state is favored because of the nephelauxetic effect, i.e., smaller pairing energy in Fe(III) complex. Our results show that the difference in the electronic structure of the two complexes, i.e., different spin-ground states, directly affects these molecules' structure, magnetism, reactivity, and biological activities.", publisher = "Viena, Austria : Institute of Applied Synthetic Chemistry, TU Wien, ChemIT e.U.", journal = "6th EuChemS Inorganic Chemistry Conference, September 3 – 7, 2023, Institute of Applied Synthetic Chemistry, TU Wien, Austria", title = "Spin states of Mn(II) and Fe(III) complexes with thiosemicarbazone", pages = "PO-133-PO-133", url = "https://hdl.handle.net/21.15107/rcub_cer_6570" }
Savić, M., Jevtović, M., Čobeljić, B., Gruden, M.,& Zlatar, M.. (2023). Spin states of Mn(II) and Fe(III) complexes with thiosemicarbazone. in 6th EuChemS Inorganic Chemistry Conference, September 3 – 7, 2023, Institute of Applied Synthetic Chemistry, TU Wien, Austria Viena, Austria : Institute of Applied Synthetic Chemistry, TU Wien., PO-133-PO-133. https://hdl.handle.net/21.15107/rcub_cer_6570
Savić M, Jevtović M, Čobeljić B, Gruden M, Zlatar M. Spin states of Mn(II) and Fe(III) complexes with thiosemicarbazone. in 6th EuChemS Inorganic Chemistry Conference, September 3 – 7, 2023, Institute of Applied Synthetic Chemistry, TU Wien, Austria. 2023;:PO-133-PO-133. https://hdl.handle.net/21.15107/rcub_cer_6570 .
Savić, Milica, Jevtović, Mima, Čobeljić, Božidar, Gruden, Maja, Zlatar, Matija, "Spin states of Mn(II) and Fe(III) complexes with thiosemicarbazone" in 6th EuChemS Inorganic Chemistry Conference, September 3 – 7, 2023, Institute of Applied Synthetic Chemistry, TU Wien, Austria (2023):PO-133-PO-133, https://hdl.handle.net/21.15107/rcub_cer_6570 .