Tartrate bridging ligands in divalent Co(II)/Co(III) dinuclear anion

Kozlevčar, Bojan (avtor), Tihomirović, Maja (avtor), Počkaj, Marta (avtor), Jagličić, Zvonko (avtor)

A cobalt(II/III) ionic compound with bridging tartaric acid ($H_4L$) anion ($CH_6N_3)3[Co_2^{II/III}(L)_2(H_2O)_2]·4H_2O$ 1 was synthesized. The crystallites were isolated from highly alkaline aqueous solution in the presence of guanidinium cations ($CH_6N_3)^+$ being then incorporated as counter ions. A determined structure reveals the dinuclear coordination anion with two cobalt centers, each within its distinctive coordination octahedron $CoO_6$ sphere showing different Co−O bond lengths. The metal center with shorter coordination bonds is assigned as Co(III), while the other with Co(II), all in agreement with overall net charge equilibrium. This involves three guanidinium cations, two tartrate(4-) anions, the latter within the coordination anion, as well as with bond valence sums for both cobalt centers. Both tartrates (L) are triply bonded on the Co(III) center, thus enabling $Co^{III}O_6$ coordination bonds. On the other hand, only two coordination bonds are enabled by each tartrate towards Co(II), while the remaining two in $Co^{II}O_6$ are completed by two terminal water molecules. The electronic spectrum shows clearly the d-d bands at 400 and 665 nm for Co(III), while at 520 nm for Co(II), for each CoO6, respectively. The temperature dependent magnetic susceptibility shows the paramagnetic behavior of the compound, due to the $d^7$ Co(II) ions being in a high spin state, while the $d^6$ low spin Co(III) ions are diamagnetic.

• Jezik: Angleški jezik
• Ključne besede: cobalt, tartrate, guanidine, structure, magnetism
• Vrsta gradiva: Izvleček
• Tipologija: 1.01 - Izvirni znanstveni članek
• Organizacija: FKKT - Fakulteta za kemijo in kemijsko tehnologijo ; FGG - Fakulteta za gradbeništvo in geodezijo
• Status publikacije: Objavljeno
• Različica publikacije: Objavljena publikacija
• Datum objave: 01.01.2024
• Leto izida: 2024
• Št. strani: 11 str.
• Številčenje: Vol. , art. 116797
• PID: 20.500.12556/RUL-153183
• UDK: 546.73:547.476.3-38
• ISSN pri članku: 0277-5387
• DOI: 10.1016/j.poly.2023.116797
• COBISS.SI-ID: 178257155
• Datum objave v RUL: 20.12.2023

Gradivo je del revije

• Naslov: Polyhedron
• Skrajšan naslov: Polyhedron
• Založnik: Elsevier
• ISSN: 0277-5387
• COBISS.SI-ID: 26153984

Licence

• Licenca: CC BY-NC-ND 4.0, Creative Commons Priznanje avtorstva-Nekomercialno-Brez predelav 4.0 Mednarodna
• Povezava: http://creativecommons.org/licenses/by-nc-nd/4.0/deed.sl
• Opis: Najbolj omejujoča licenca Creative Commons. Uporabniki lahko prenesejo in delijo delo v nekomercialne namene in ga ne smejo uporabiti za nobene druge namene.

Sekundarni jezik

• Jezik: Slovenski jezik
• Ključne besede: kobalt, tartrat, gvanidin, struktura, magnetizem

Projekti

• Financer: ARRS - Agencija za raziskovalno dejavnost Republike Slovenije
• Številka projekta: P1-0175
• Naslov: Napredna anorganska kemija

• Financer: ARRS - Agencija za raziskovalno dejavnost Republike Slovenije
• Številka projekta: P2-0348
• Naslov: Nove slikovno-analitske metode