TY - JOUR
T1 - Synthesis and characterization of T[Ni(CN)4]·2pyz with T=Fe, Ni; Pyz=pyrazine
T2 - Formation of TpyzNi bridges
AU - Lemus-Santana, A. A.
AU - Rodríguez-Hernández, J.
AU - González, M.
AU - Demeshko, S.
AU - Ávila, M.
AU - Knobel, M.
AU - Reguera, E.
PY - 2011/8
Y1 - 2011/8
N2 - The formation of TpyzNi bridges (pyz=pyrazine) in the T[Ni(CN) 4]·2pyz series is known for T=Mn, Zn, Cd and Co but not with T=Fe, Ni. In this contribution the existence of such bridges also for T=Fe, Ni is discussed. The obtained pillared solids, T[Ni(CN)4]·2pyz, were characterized from XRD, TG, UVVis, IR, Raman, Mössbauer and magnetic data. Their crystal structures were refined in the orthorhombic Pmna space group from XRD powder patterns. The structural behavior of these solids on cooling down to 77 K was also studied. In the 180200 K temperature range the occurrence of a structural transition to a monoclinic structure (P21/c space group) was observed. No temperature induced spin transition was observed for Fe[Ni(CN)4]·2pyz. The iron (II) was found to be in high spin electronic state and this configuration is preserved on cooling down to 2 K. The magnetic data indicate the occurrence of a low temperature weak anti-ferromagnetic interaction between T metal centers within the T[Ni(CN) 4] layer. In the paramagnetic region for Ni[Ni(CN) 4]·2pyz, a reversible temperature induced spin transition for the inner Ni atom was detected.
AB - The formation of TpyzNi bridges (pyz=pyrazine) in the T[Ni(CN) 4]·2pyz series is known for T=Mn, Zn, Cd and Co but not with T=Fe, Ni. In this contribution the existence of such bridges also for T=Fe, Ni is discussed. The obtained pillared solids, T[Ni(CN)4]·2pyz, were characterized from XRD, TG, UVVis, IR, Raman, Mössbauer and magnetic data. Their crystal structures were refined in the orthorhombic Pmna space group from XRD powder patterns. The structural behavior of these solids on cooling down to 77 K was also studied. In the 180200 K temperature range the occurrence of a structural transition to a monoclinic structure (P21/c space group) was observed. No temperature induced spin transition was observed for Fe[Ni(CN)4]·2pyz. The iron (II) was found to be in high spin electronic state and this configuration is preserved on cooling down to 2 K. The magnetic data indicate the occurrence of a low temperature weak anti-ferromagnetic interaction between T metal centers within the T[Ni(CN) 4] layer. In the paramagnetic region for Ni[Ni(CN) 4]·2pyz, a reversible temperature induced spin transition for the inner Ni atom was detected.
KW - Crystal chemistry
KW - Layered compound
KW - Pillared solid
KW - Spin transition
KW - Structural study
UR - http://www.scopus.com/inward/record.url?scp=79960696687&partnerID=8YFLogxK
U2 - 10.1016/j.jssc.2011.06.011
DO - 10.1016/j.jssc.2011.06.011
M3 - Artículo
SN - 0022-4596
VL - 184
SP - 2124
EP - 2130
JO - Journal of Solid State Chemistry
JF - Journal of Solid State Chemistry
IS - 8
ER -