Magnetic Isolation of the Linear Trinuclear Anion in [Cu(Him)6] Cu(Him)4[Cu(μ-EDTA)(Him)]2·6H2O (1) as the Novel Imidazolium(+) Salt (H2im)2[Cu(Him)4(µ-EDTA)Cu(Him)2]·2H2O (2)—A Comparative Look to Their Crystal Structures, Thermal, Spectral and Magnetic Properties and DFT Calculations | Publicación