A new [Fe(L)2(NCS)2] complex with Δ- and Λ-type molecular sites exhibiting incomplete spin crossover
Inorganic Chemistry Communications, cilt.191, sa.P3, 2026 (SCI-Expanded, Scopus)
- Yayın Türü: Makale / Tam Makale
- Cilt numarası: 191 Sayı: P3
- Basım Tarihi: 2026
- Doi Numarası: 10.1016/j.inoche.2026.117186
- Dergi Adı: Inorganic Chemistry Communications
- Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Chemical Abstracts Core, Chimica, DIALNET
- Anahtar Kelimeler: Magnetic property, Phase transition, Stereoisomerism
- Çukurova Üniversitesi Adresli: Evet
Özet
[Fe(Ls-Bu)2(NCS)2] (Ls-Bu = racemic N-(pyridin-2-ylmethylidene)-4-sec-butylaniline) exhibits 50% incomplete spin crossover at T1/2 = 155(1) K. Single-crystal X-ray diffraction analysis revealed two crystallographically independent Fe2+ sites in the monoclinic P21/n lattice (Z' = 2) with Δ- and Λ-type molecular configurations. The sec-butyl substituents are statistically disordered with nearly equal occupancies, indicating a nearly random distribution of ligand stereoisomers. Despite their similar electronic structures, distinct octahedral distortions at the FeN6 centers lead to different spin-transition behaviors. Structural analyses suggest that angular distortion is more important than bond-length distortion in differentiating the spin states, and the more angularly distorted site remains in the high-spin state at low temperature.