Field-induced slow relaxation of magnetization in dinuclear and trinuclear Co-III ... Mn-III complexes

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F61989592%3A15310%2F16%3A33161064" target="_blank" >RIV/61989592:15310/16:33161064 - isvavai.cz</a>

Výsledek na webu

<a href="http://pubs.rsc.org/en/content/articlehtml/2016/ra/c5ra23922b" target="_blank" >http://pubs.rsc.org/en/content/articlehtml/2016/ra/c5ra23922b</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1039/c5ra23922b" target="_blank" >10.1039/c5ra23922b</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Field-induced slow relaxation of magnetization in dinuclear and trinuclear Co-III ... Mn-III complexes

Popis výsledku v původním jazyce

Two new dinuclear, [Co(3EtO-L5)(mu-CN) Mn(L4a) Cl] (1) and [Co(3EtO-L5)(mu-CN) Mn(L4a) Br] (2), and two trinuclear [{Co(3EtO-L5)(mu-CN)}(2)Mn(L4a)]I (3) and [{Co(3EtO-L5)(mu-CN)}(2)Mn(L4a)](NO3) (4) complexes were prepared and thoroughly characterized (H(2)3EtO-L5 N, N'-bis(3-ethoxy-2-hydroxybenzylidene)-1,6- diamino-3-azahexane, L4a(2-) = N, N'-ethane-bis(salicylideneiminate) dianion). The crystal structures were determined for all four compounds, while the static and dynamic magnetic properties were studied only for compounds 1-3. It has been revealed by simultaneous fitting of temperature and field dependent magnetic data and by using the spin Hamiltonian formalism involving the axial anisotropy term that the manganese(III) atoms possess relatively large and negative axial magnetic anisotropy in 1-3, with D = -3.9(2) cm(-1) in 1, -4.9(2) cm(-1) in 2, and -4.1(1) cm(-1) in 3. These results were supported by ab initio CASSCF calculations which were in good agreement with the experimental ones, however, a small rhombicity was calculated contrary to the experimental evaluations: D-calc(E-calc/D-calc) = -3.2 cm(-1) (0.04) in 1, -3.0 cm(-1) (0.03) in 2, and -3.6 cm(-1) (0.04) in 3. The measurements of dynamic magnetic data confirmed that compounds 1-3 represent a new type of Mn(III) field-induced single-ion magnet. The peak maxima of the frequency dependent out-phase susceptibility were below the lowest accessible temperature in all the three cases (i. e. below 1.9 K) and this prevented us from the construction of the Argand diagram. Nevertheless, the approximate procedure for extracting the spin-reversal barrier (U-eff) and relaxation time (tau(0)) was used, and the values of U-eff ranging from 11 to 20 K and t(0) from 0.1 to 19 x 10(-7) s were obtained.

Název v anglickém jazyce

Field-induced slow relaxation of magnetization in dinuclear and trinuclear Co-III ... Mn-III complexes

Popis výsledku anglicky

Two new dinuclear, [Co(3EtO-L5)(mu-CN) Mn(L4a) Cl] (1) and [Co(3EtO-L5)(mu-CN) Mn(L4a) Br] (2), and two trinuclear [{Co(3EtO-L5)(mu-CN)}(2)Mn(L4a)]I (3) and [{Co(3EtO-L5)(mu-CN)}(2)Mn(L4a)](NO3) (4) complexes were prepared and thoroughly characterized (H(2)3EtO-L5 N, N'-bis(3-ethoxy-2-hydroxybenzylidene)-1,6- diamino-3-azahexane, L4a(2-) = N, N'-ethane-bis(salicylideneiminate) dianion). The crystal structures were determined for all four compounds, while the static and dynamic magnetic properties were studied only for compounds 1-3. It has been revealed by simultaneous fitting of temperature and field dependent magnetic data and by using the spin Hamiltonian formalism involving the axial anisotropy term that the manganese(III) atoms possess relatively large and negative axial magnetic anisotropy in 1-3, with D = -3.9(2) cm(-1) in 1, -4.9(2) cm(-1) in 2, and -4.1(1) cm(-1) in 3. These results were supported by ab initio CASSCF calculations which were in good agreement with the experimental ones, however, a small rhombicity was calculated contrary to the experimental evaluations: D-calc(E-calc/D-calc) = -3.2 cm(-1) (0.04) in 1, -3.0 cm(-1) (0.03) in 2, and -3.6 cm(-1) (0.04) in 3. The measurements of dynamic magnetic data confirmed that compounds 1-3 represent a new type of Mn(III) field-induced single-ion magnet. The peak maxima of the frequency dependent out-phase susceptibility were below the lowest accessible temperature in all the three cases (i. e. below 1.9 K) and this prevented us from the construction of the Argand diagram. Nevertheless, the approximate procedure for extracting the spin-reversal barrier (U-eff) and relaxation time (tau(0)) was used, and the values of U-eff ranging from 11 to 20 K and t(0) from 0.1 to 19 x 10(-7) s were obtained.

Druh

J_x - Nezařazeno - Článek v odborném periodiku (Jimp, Jsc a Jost)

CEP obor

CA - Anorganická chemie

OECD FORD obor

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Projekt

<a href="/cs/project/LO1305" target="_blank" >LO1305: Rozvoj centra pokročilých technologií a materiálů</a><br>

Návaznosti

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Rok uplatnění

2016

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

RSC Advances (online)

ISSN

2046-2069

e-ISSN

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Svazek periodika

6

Číslo periodika v rámci svazku

4

Stát vydavatele periodika

GB - Spojené království Velké Británie a Severního Irska

Počet stran výsledku

10

Strana od-do

3074-3083

Kód UT WoS článku

000368193500065

EID výsledku v databázi Scopus

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