Three coordination polymers constructed from bis(imidazol-l-yl-methyl)benzene: syntheses, structures, and third-order nonlinear optical properties

• Published in: Transition metal chemistry (Weinheim) 2015-02, Vol.40 (1), p.11-19
• Main Authors: Zhao, Ning, Deng, Yue-E., Liu, Ping, An, Cai-Xia, Wang, Tian-Xi, Lian, Zhao-Xun
• Format: Article
• Language: English
• Subjects: Absorptivity; Catalysis; Chains; Chemistry; Chemistry and Materials Science; Construction; Coordination polymers; Inorganic Chemistry; Ligands; Links; Mathematical analysis; Nonlinearity; Optical properties; Organometallic Chemistry; Physical Chemistry
• ISSN: 0340-4285; 1572-901X
• DOI: 10.1007/s11243-014-9884-z

Three coordination polymers, {[Ni(H 2 O) 2 (bib) 2 ]-(H 2 BTA)·2H 2 O} n ( 1 ), {[Co 2 (bib) 2 (BTA)]·H 2 O} n ( 2 ), and {[Co 2 (bib) 2 (CA) 2 ]·H 2 O} n ( 3 ), (H 4 BTA = biphenyl-3,3′,4,4′-tetracarboxylic acid; bib = 1, 2-bis(imidazol-l-yl-methyl)benzene; H 2 CA = camphanic acid), have been synthesized under hydrothermal conditions. In complex 1 , bib serves a bridging ligand to link two Ni(II) atoms into an infinite joint-like chain. In 2 , binuclear units are connected by BTA and bib ligands to form 2-D sheets. In 3 , each Ni(II) atom is coordinated with two bib ligands to give a 22-membered ring, which is further linked by CA ligands to form a ladder-like chain. The third-order nonlinear optical (NLO) properties of the complexes were determined by Z-scan technique in DMSO solution. All three complexes exhibit strong third-order NLO absorption with absorptive coefficients β(MKS) 1.44 × 10 −10  m W −1 for 1 , 1.68 × 10 −10  m W −1 for 2 , and −6.31 × 10 −10  m W −1 for 3 , respectively, of which compound 3 shows saturable absorption. The third-order NLO susceptibilities | χ (3) | were calculated as 0.32 × 10 −10 for 1 , 0.37 × 10 −10 for 2 , and 1.39 × 10 −10  esu for 3 , while the hyperpolarizabilities γ ′ are 9.95 × 10 −29 for 1 , 5.85 × 10 −29 for 2 and 4.64 × 10 −28  esu for 3 , respectively.