Two new canted antiferromagnetic systems: magnetic, theoretical, and crystallographic studies on trans-bis(2-iodopyridine)dihalocopper(ii)

Abstract

The two complexes Cu(2iP)X2 were prepared (where 2ip =2-iodopyridine and X = Cl or Br), and their crystal structures were determined. The two complexes are isomorphous and form a magnetic...

Polymorphism and isomorphism in trans-bis(2,5-diiodopyridine)dihalocopper(ii) complexes: theoretical and crystallographic studies

“…The two crystal structures of [Cu(2Ipy) 2 X 2 ] complexes are isomorphous, the Cu⋯I2 distance is shorter in the bromide complex than in the chloride complex by 0.01 Å and 0.02 Å at room temperature and 150 K, respectively. 51,52 The difference is more pronounced in complexes [Cu(2Brpy) 2 X 2 ] and [Cu(2Clpy) 2 X 2 ], thus we find that the Cu⋯Br distance is shorter in bromide complexes than in chloride complexes, by 0.116 Å in [Cu(2BrPy) 2 X 2 ] and 0.041 in [Cu(2Clpy) 2 X 2 ]. 49,50…”

“…2 and 3. 49–51,61,62 The Cu⋯I2 distances are significantly shorter in PI-Br and PII-Br than the corresponding distance in their isostructural polymorph (PI-Cl) by 0.035 Å (Table 2). The distance is significantly longer in PII-Cl by 0.150 Å (Table 2).…”

“…Experimentally, [Cu(2Clpy) 2 X 2 ] crystallizes as the syn-conformer, whereas, [Cu(2Brpy) 2 X 2 ] and [Cu(2Ipy) 2 X 2 ] crystallize as anti-conformer. [49][50][51][52] It is noteworthy that the [Cu(2Br5Mpy) 2 X 2 ] (2Br5Mpy = 2-bromo-5methylpyridine) crystallizes as the anti-conformer. 53 In this article, we report the crystal structures of both conformers (syn-and anti-conformers) of [Cu(25dIpy) 2 Cl 2 ] where 25dIpy = 2,5-diiodopyridine.…”

Halogen bond and polymorphism in trans-bis(2-iodo-5-halopyridine)dihalocopper(ii) complexes: crystallographic, theoretical and magnetic studies

“…11). 16,67 These magnetic chains run parallel to the a-axis. As the organic halogen gets heavier the inter-chloride distance increases, and hence a weaker spin exchange is observed (Fig.…”

“…Cu(2ClP) 2 X 2 crystallizes as syn-conformer whereas Cu(2BrP) 2 X 2 and Cu(2IP) 2 X 2 crystallize as anti-conformers. 19,64,67,68 All our attempts to crystallize syn-conformers from either Cu(2BrP) 2 X 2 or Cu(2IP) 2 X 2 have been unsuccessful, 40 even though calculations indicated that the syn-conformer is more stable than the anti-conformer. Cu(2Br5MP) 2 X 2 crystallize as anti-conformers (2Br5MP = 2-bromo-5-methylpyridine).…”