| In view of the fact that the study of guanidinate (amidinate) based organometallic complexes mainly focus on their synthesis, structure and reaction behavior, the luminescent properties of these complexes have not been reported yet, and little attention was paid to study the luminescent properties of zirconium complexes. A serial of guanidinate (amidinate) based zirconium and lanthanide complexes were synthesized and fully characterized, and their luminescent properties were studied. Meanwhile, five benzothiazole-2-thiolate based lanthanide complexes were synthesized and their luminescent properties were studied. 1. The luminescent properties of amidinate based zirconium complexes [iPrNC(Ph)NiPr]2ZrBr2 (1), [CyNC(Ph)NCy]2ZrBr2 (2), [Me3SiNC(Ph-p-Cl)NSiMe3]2 -ZrCl2 (4) and [Me3SiNC(Ph)N(CH2)3NC(Ph)NSiMe3]ZrCl2·THF (5) were studied. All theses complexes were characterized by elemental analysis, IR and 1H-NMR spectroscopy, complexes 1, 4 and 5 were further characterized by X-ray determination. Under ultraviolet light excitation, all the four complexes were found to exhibit intense green emission (λem 450-530 nm) in the solid state both at room temperature and at 77 K. Lifetime of these complexes are around 0.02 ms. 2. The luminescent properties of guanidinate based zirconium complexes [iPrNC(NiPr2)NiPr]2ZrCl2 (9), [CyNC(NiPr2)NCy]2ZrCl2 (10), {iPrNC[N(CH2)5]-NPri}2ZrCl2 (11), {CyNC[N(CH2)5]NCy}2ZrCl2 (12) and [iPrNC(NC12H8)NPri]2ZrCl2 (14) were studied. All theses complexes were characterized by elemental analysis and IR spectroscopy, complexes 9-12 were further characterized by 1H-NMR spectroscopy and X-ray determination. Under ultraviolet light excitation, all the five complexes were found to exhibit intense green emission (λem 500 nm) in the solid state. Lifetime of these complexes are around 0.02 ms. 3. Two zirconium complexes [iPrNC(NiPr2)NiPr]2ZrCl2 (9) and (C12H8N)2ZrCl2(THF)2 (13) were found to have triboluminescent character, and it is the first time to find early transition metal complexes have triboluminescent character. Luminescence properties studies show that the triboluminescent spectrum of complex 9 is very similar to it's photoluminescence spectrum. The λem of TL is 10 nm smaller than the PL's. 4. The luminescent properties of guanidinate based lanthanide complexes [iPr2NC (NiPr)2]3Tb (15), [iPr2NC (NCy)2]3Tb (16), [(CH2)5NC(NiPr)2]3Tb (17), [(CH2)5NC(NCy)2]3Tb (18), [iPr2NC(NiPr)2]2TbCl(LiCl)(THF)2 (19), [(CH2)5NC-(NCy)2]2Tb(μ-Cl)2Li(THF)2 (20), [(CH2)5NC(NiPr)2]3Eu (21) and [iPr2NC(NiPr)2]3Eu (22) were studied. All theses complexes were characterized by elemental analysis and IR spectroscopy, complexes 15, 17 and 20 were further characterized by X-ray determination. Under ultraviolet light excitation, complexes 15-20 were found to exhibit intense green emission. All of the spectra display strong green luminescence with four emission bands at 485, 546, 585, and 624 nm, respectively, no the broad band from the ligand was obversed. These results indicated an efficiency energy transfer from the guanidinate ligand state to the emitting 5D4 level of the Tb3+ ion occurs. The four bands are correspond to the characteristic emission from the 5D4-7FJ (J = 6; 5; 4; 3) transition of Tb3+ ion. Among them the 5D4-7F5 transition exhibits the strongest one. Their lifetime are in the range of 1 to 7 ms. Different guanidinate ligand has effect on the strong of the luminescence, the figure of the emission spectrum and the lifetime of these guanidinate based terbium complexes. The number of the guanidinate ligand has effect on the strong of the luminescence but little on the lifetime of these complexes. The luminescent properties of complex 21 is better than that of complex 22. Under ultraviolet light excitation, complexes 21 and 22 were found to exhibit intense red emission. All of the spectra display five emission bands at 579, 592, 613, 650 and 624 nm, respectively, corresponding to the characteristic emission from the 5D0-7FJ (J = 0; 1; 2; 3, 4) transition of Eu3+ ion. Among them the 5D0-7F2 transition exhibits the strongest one. Complex [iPr2NC(NiPr)2]3Sm (23) cannot exhibit the characteristic orange emission of Sm3+. 5. The luminescent properties of amidinate based lanthanide complexes [ButC(NiPr)2]3Tb (24) , [ButC(NCy)2]3Tb (25) , [PhC(NiPr)2]3Tb (26) and [PhC(NCy)2]3Tb (27) were studied. The emission spectra of complexes 24 and 25 display strong green luminescence with four emission bands at 498 (5D4-7F6), 548 (5D4-7F5), 588 (5D4-7F4), and 622 nm (5D4-7F3), respectively. Meanwhile, the band from the ligand was also obversed, it indicated that the efficiency of energy transfer from the guanidinate ligand state to the emitting 5D4 level of the Tb3+ ion is better than that of amidinate. Lifetime of complexes 24 and 25 are around 9 ms. Study results show that the luminescence properties of complexes 24 and 25 are much better than that of 26 and 27. 6. The luminescent properties of thiolate-benzothiazole based lanthanide complexes (MBT)3Tb(THF)2·THF (28), (MBT)3Sm(THF)2·THF (29), (5-ClMBT)3-Tb(THF)2·THF (31) and (5-ClMBT)3Sm(THF)2·THF (32) were studied. Due to an efficient energy transfer from the ligand to the central metal ions, complexes 28 and 31 show a strong green emission around 498, 548, 588, 622 nm, corresponding to Tb3+ 5D4-7FJ (J = 6, 5, 4, 3) transitions, complex 29 and 32 show high orange luminescence characteristic around 565, 605, 650 and 705 nm, arising from the Sm3+ 4G5/2-6HJ (J = 5/2, 7/2, 9/2, 11/2). In the emission spectrum of complex 28, 5D4-7F2 (650), 5D4-7F1 (670) and 5D4-7F0 (680 nm) transitions of Tb3+ were also observed. Lifetimes of complexes 28-31 are 0.4, 0.2, 2.6 and 0.78 ms, respectively. Complex Eu(MBT)3(THF)2·(THF) (30) can not exhibit the characteristic red emission of Eu3+.
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