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One Ni(II)-Na(I) complex namely {[NiII-L-NaI(dca)]2}n [H2L = 1,2-ethanediylbis(2-iminomethylene-6-methoxy-phenol)] was synthesized under mild conditions at room temperature and characterized by elemental analysis, infrared spectroscopy, X-ray diffraction and thermogravimetric analysis. Single crystal X-ray diffraction analyses show that Ni(II) centers are in four-coordinate D4h geometry and Na(I) centers are in a six-coordinate slightly distorted pentagonal pyramidal C5v geometry in the complex. The basic structural components of the complex are the [NiII-L-NaI] units, which are further connected by the dicyanamide through μ1,5 mode between the Na centers to form 1D chain structures. Thermogravimetric analysis indicate that complex 1 shows good thermal stability. [ABSTRACT FROM AUTHOR]

• The utilization of organic Schiff base ligands H 2 valen, and organic sulfonate ligands Na(4-HBS) towards Mn(Ac) 3 ⋅2H 2 O leads to the formation of one-dimensional coordination polymer. • complex 1 exhibits single ion magnet (SIM) behaviour under a direct current (dc) field. • This research reports not only a rare Mn(III) SIM molecular complex but also provide a potential approach to construct SIM chains. The synthesis using organic Schiff base ligands H 2 valen, and organic sulfonate ligands Na(4-HBS) in conjunction with Mn(Ac) 3 ⋅2H 2 O, produces a one-dimensional coordination polymer with the formula {[M n (valen)N a (4-HBS) 2 ]⋅2CH 3 OH} n (1) [H 2 valen=6,6′-((1E,1′E)-(ethane-1,2-diylbis(azaneylylidene))bis(methaneylylidene))bis(2-methoxyphenol); Na(4-HBS)= Sodium 4-hydroxybenzenesulfonate]. Single crystal X-ray diffraction analysis reveals that complex 1 consist of neutral chains with one [Mn(valen)Na]2+ and two 4-HBS−moieties, in which the Mn(III) adopts an elongated octahedral geometry and Na(I) adopts a distorted pentagonal pyramid geometry, respectively. Magnetic investigations indicate the important magnetic anisotropy in the six-coordinated Mn(III) with the zero-field splitting parameter D = -3.2 cm−1. AC measurements suggest that complex 1 displays characteristics of slow magnetic relaxation under a 2000 Oe DC field, indicative of single ion magnet (SIM) behaviour. The effective energy barriers and the pre-exponential factor for complex 1 are determined to be 10.5 cm−1, and 1.36 × 10−7 s, respectively. This research reports not only a rare Mn(III) SIM molecular complex but also provide a potential approach to construct SIM chains. [Display omitted] [ABSTRACT FROM AUTHOR]

In this work, two new three-dimensional Co(II) metal-organic frameworks (MOFs), {[Co 2 (TFBA)(4,4′-bpy)H 2 O]·5DMF·7H 2 O} n (CoMOF-1) and {[Co 2 (TFBA)(bpen)H 2 O] ·6DMF·6H 2 O } n (CoMOF-2) (H 3 TFBA = tris(3′-F-4′-carb oxybiphenyl)amine, 4,4′-bpy = 4,4′-bipyridine, bpen = trans -1,2-bis(4-pyridyl)ethene) were constructed by a solvothermal method. Both CoMOF-1 and CoMOF-2 displayed similar 3D frameworks with the 2, 3, 4, 6-c net topology based on dinuclear [Co 2 O 8 ] units. The powder X-ray diffraction (PXRD) results and thermogravimetric analysis (TGA) proved that CoMOF-1 and CoMOF-2 have good structural and thermal stability. As we expected, the luminescence sensing investigations demonstrated that CoMOF-1 and CoMOF-2 could be considered as promising luminescent sensors toward Cu2+, Fe3+ and Cr 2 O 7 2− ions via a quenching effect, with high sensitivity and good reusability. Additionally, the possible luminescent quenching reasons were systematically studied by UV spectroscopy, X-ray photoelectron spectroscopy (XPS), IR spectra and PXRD patterns. [Display omitted] In this work, two new three-dimensional Co(II) metal-organic frameworks (MOFs), {[Co 2 (TFBA)(4,4′-bpy)H 2 O]·5DMF·7H 2 O} n (CoMOF-1) and {[Co 2 (TFBA)(bpen)H 2 O] ·6DMF·6H 2 O } n (CoMOF-2) (H 3 TFBA = tris(3′-F-4′-carb oxybiphenyl)amine, 4,4′-bpy = 4,4′-bipyridine, bpen = trans -1,2-bis(4-pyridyl)ethene) were constructed by a solvothermal method. Both CoMOF-1 and CoMOF-2 displayed similar 3D frameworks with the 2, 3, 4, 6-c net topology based on dinuclear [Co 2 O 8 ] units. The powder X-ray diffraction (PXRD) results and thermogravimetric analysis (TGA) proved that CoMOF-1 and CoMOF-2 have good structural and thermal stability. As we expected, the luminescence sensing investigations demonstrated that CoMOF-1 and CoMOF-2 could be considered as promising luminescent sensors toward Cu2+, Fe3+ and Cr 2 O 7 2− ions via a quenching effect, with high sensitivity and good reusability. Additionally, the possible luminescent quenching reasons were systematically studied by UV spectroscopy, X-ray photoelectron spectroscopy (XPS), IR spectra and PXRD patterns. [ABSTRACT FROM AUTHOR]