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A new 3D complex namely [Gd 4 (C 7 H 7 N 2 O 4) 6 (H 2 O) 12 ·Cl 6 ·9H 2 O (1) was solvothermally synthesized by using 1,3-bis (carboxymethyl) imidazolium cation as a ligand. Single crystal X-ray analysis reveals that 3D positive charged framework was formed by Gd–O coordination bonds,and Gd3+ ions have two kinds of coordination environments. The free counter Cl− ions and lattice H 2 O locate in cavities of 1 through extensive H-bonds and electrostatic attractions between the Cl−/H 2 O and the positive framework. The thermogravimetric analysis (TGA) shows the organic framework decomposed at temperature above 345 °C, giving the final products Gd 2 O 3. The temperature dependent magnetic susceptibility displays antiferromagnetic interaction at temperature below 15.2 K, once above 15.2 K, compound 1 converts into paramagnetic interaction. The gadolinium-based MOF with 1, 3-bis(carboxymethyl)imidazolium Chloride ionic liquid as ligand has good thermal stability and magnetic property. There is Neel temperature at 15.2 K in compound 1 when study its magnetic, at temperature below 15.2 K there is antiferromagnetic interaction, but at temperature above 15.2 K, it converts into paramagnetic interaction. Image 1 1. This structure has 3D positive charged framework was formed by Gd−O coordination bonds. 2. There are free counter Cl− ions and lattice H 2 O locate in cavities of 1 through extensive H−bonds and electrostatic attractions between the Cl−/H 2 O and the positive framework. 3. The organic framework can be kept stables until 345 °C. There are antiferromagnetic interaction in Gd3+ ions at temperature below 15.2 K, once above 15.2 K, they converts into paramagnetic interaction. [ABSTRACT FROM AUTHOR]

A new lanthanide metal organic framework, namely [Eu(C 7 H 7 O 4 N 2)(H 2 O) 2 (Cl 0.38) 2 Cl 1.24 (1), was solvothermally synthesized using 1,3-bis(carboxymethyl)imidazolium chloride ([H 2 imdc]Cl) ionic liquid as a ligand. This compound was structurally characterized by single crystal X-ray diffraction and its properties were analyzed spectroscopy and theoretical studies. In 1 , Eu (III) ions have only one coordination environment, and the ligands exhibit one coordination mode. The Eu3+ ions and ligands are connected to construct wavelike 2D cationic layers through coordination bonds, and then the 2D networks further interconnected through hydrogen bonds. The luminescent properties were studied at 77 K. The emission spectrum shows that there is one Eu3+ ion site in asymmetric unit, which is consistent with the results of the X-ray crystal structure analysis. Compound 1 exhibits characteristic emission bands of Eu3+ with emission lifetime of 0.336 ms. Single crystal of metal organic framework: [Eu(C 7 H 7 O 4 N 2)(H 2 O) 2 (Cl 0.38) 2 Cl 1.24 1 was solvothermally synthesized by 1,3-bis(carboxymethyl)imidazolium ionic liquid. The single crystal data indicate Eu3+ ions have only one nine-coordinate chemical environment, which is accordance with the results of the luminescence analysis of 1. FT-IR, PXRD, thermogravimetric analysis are also in accordance with the result of single crystal structure data. The time-resolved spectra further display that there is only one Eu3+ ion site in 1 and it has the lifelime of 0.336 ms. The thermal analysis results show the organic framework of 1 can sustain until 299 °C and completely decomposed into Eu 2 O 3 at about 589 °C. Image 1 • Rare earth metal organic framework crystal was synthesized by solvothermal method using ionic liquids as ligand. • The synthesized Eu-MOF is 2D cationic layers, which are further interconnected through hydrogen bonds. • It has good optical properties and the fluorescence lifetime can reach 0.336 ms. [ABSTRACT FROM AUTHOR]

• Four-coordinate N -heterocyclic carbene (NHC) Cu(I) complexes having the pyridyl-imidazolylidene ligand are synthesized and characterized. • The photophysical properties of the resulting complexes is investigated. • Complexes show yellow-green emission in 543–555 nm region with the higher photoluminescence efficiency. • DFT and TDDFT calculations are taken to support the differences of the photophysical properties. The synthesis, characterization and photophysical properties of a series of the four-coordinate N -heterocyclic carbene (NHC) copper(I) complexes are reported. These NHC-Cu(I) complexes contain two bidentate ligands, the R -substituted pyridyl-imidazolylidene-type ligand and diphosphine ligand bis [(2-diphenylphosphino)phenyl] ether (POP). The photophysical properties of these complexes can be adjusted depending on the nature of substituents at 4-position of the phenyl ring in the NHC ligand. The metal-to-ligand charge transfer (MLCT) absorption band can be observed for all complexes at 348–362 nm, and the emission wavelengths can be fine-tuned to cover the spectral range of 543–555 nm with the higher photoluminescence efficiency of up to 66.2% in the solid state. Density functional theory (DFT) and time dependent density functional theory (TDDFT) calculations were employed to support potophysical properties of the NHC-Cu(I) complexes. [Display omitted] [ABSTRACT FROM AUTHOR]

• Four-coordinate N-heterocyclic carbene (NHC) Cu(I) complexes bearing different diphosphine ligands are synthesized and characterized. • The photophysical properties of the resulting complexes is investigated. • Complexes show yellow-green emission in 525–555 nm region with the phosphorescent origin. • The differences of the photophysical properties were rationalized by DFT and TDDFT calculations. Here, we report a series of the four-coordinate N-heterocyclic carbene (NHC) copper(I) complexes having the same bidenate NHC ligand and different bisphosphine (P^P) ligands, [Cu(CNbenPy-benzIm)(Naphphos)]PF 6 (P1), [Cu(CNbenPy-benzIm)(cyc-xantphos)]PF 6 (P2), and [Cu(CNbenPy-benzIm)(xantphos)]PF 6 (P3), (CNbenPy-benzIm = 3-(3-cyanobenzyl)-1-(5-phenylpyridin-2-yl)-1 H -imidazolylidene; BINAP = 2,2′-bis(diphenylphosphino)-1,1′-binaphthalene; cyc-xantphos = (9,9-dimethyl-9 H -xanthene-4,5-diyl)bis(dicyclohexylphosphine), xantphos = 9,9-dimethyl-9 H -xanthene-4,5-diyl)bis(diphenylphosphine)). P1 exhibits the metal-to-ligand charge transfer (MLCT) absorption band at 366 nm with high molar extinction coefficient of 2.44 × 104 M−1 cm−1, while P2 and P3 show a blue-shift of the MLCT absorption band at 336–341 nm with the molar extinction coefficients of 0.82–1.16 × 104 M−1 cm−1, which are just a little lower than that of P1. The emission wavelengths of all NHC-Cu(I) complexes can be fine-tuned to cover the spectral range of 525–555 nm with the phosphorescent origin in PMMA films. P1 has the lowest photoluminescence efficiency of 5.50% with the red-shifted emission wavelength at 555 nm and the emission lifetime of 237 μs, whereas P3 show the highest photoluminescence efficiency of 39.5% with the blue-shifted emission wavelength at 525 nm and the emission lifetime of 64.4 μs. The differences for photophysical properties of NHC-Cu(I) complexes were rationalized using density functional theory (DFT) and time dependent density functional theory (TDDFT) calculations. [Display omitted] [ABSTRACT FROM AUTHOR]

Three four-coordinate N-heterocyclic carbene (NHC) copper(I) complexes, [Cu(Ph-BenIm-Py)(POP)]PF 6 ( 1 ), [Cu(Naph-BenIm-Py)(POP)]PF 6 ( 2 ), and [Cu(Anthr-BenIm-Py)(POP)]PF 6 ( 3 ) (Ph-BenIm-Py = 3-benzyl-1-(pyridin-2-yl)-1 H -benzimidazolylidene, Naph-BenIm-Py = 3-(naphthalen-2-yl-1-(pyridin-2-yl)-1 H - benzimidazolylidene, Anthr-BenIm-Py = 3-(anthracen-9-yl)-1-(pyridin-2-yl)-1 H -benzimidazolylidene, and POP = bis[2-diphenylphosphino]-phenyl)ether) have been synthesized and characterized. The different aryl substituents (phenyl, naphthyl, and anthracyl groups) were introduced into NHC ligands and the corresponding photophysical properties of the complexes were systematically investigated. The absorption spectra of all NHC Cu(I) complexes show a characteristic feature of metal-to-ligand charge transfer (MLCT) in the lower-energy region. Complex 1 exhibited good photoluminescence (PL) properties companying with the high quantum yields and long excited-state lifetimes, whereas 2 and 3 with naphthyl and anthracyl groups show the low PL efficiency caused by the strong π-π stacking interactions. Density functional theory (DFT) and time dependent density functional theory (TDDFT) calculations were employed to rationalize the photophysical properties of the NHC Cu(I) complexes. [ABSTRACT FROM AUTHOR]

• Two new two dimensional metal organic frameworks namely {Er 2 [(C 9 N 2 O 4 H 11) 3 ·H 2 O·Br]Br·Cl} n (1) and {Yb 2 [(C 9 N 2 O 4 H 11) 3 (H 2 O) 2 ]Br·Cl 2 } n (2) were solvothemally synthesized with Brønsted ionic liquid as ligand. • The effects of the reaction conditions to the growth of 1 and 2 , such as temperature, reaction solvents, as well as the ratio of solvents were explored. • 1 and 2 display good thermal stability and hydrophilicity in this work. • The magnetic measure of 2 shows its antiferromagnetic interaction via the Yb/O-C-O/Yb pathways. Two lanthanide metal organic frameworks (MOFs) {Er 2 [(C 9 N 2 O 4 H 11) 3 (H 2 O)Br]Br·Cl} n (1) and {Yb 2 [(C 9 N 2 O 4 H 11) 3 (H 2 O) 2 ]Br·Cl 2 } n (2) were solvothermally synthesized using Brønsted acidic ionic liquid: 1,3-bis(1-dicarboxylatoethyl) imidazolium bromide ([H 2 bcei]Br) as ligand. The results of single crystal X-ray diffraction show that Er3+ and Yb3+ both possess two different seven-coordinated chemical environments in 1 and 2 , respectively. While coordinating to Er3+ and Yb3+, [bcei]‒ displays same coordination mode because of their similar ionic radius. Although Er3+ and Yb3+ display different chemical environments, they are all linked by [bcei]− via Ln−O coordination bonds affording two three-dimensional structures with Cl− or Br− in the frameworks through H-bonds and electrostatic interaction. Considering the effect of the reaction temperature, solvents and solvent volume ratio on the crystal growth, the optimized synthesis conditions of 1 and 2 were explored. The magnetic behaviors of 2 were measured in the temperature range 2–300 K, which reveals its antiferromagnetic interaction between Yb3+ions. [Display omitted] [ABSTRACT FROM AUTHOR]

Three N,N-bidentate ligands, 2-phenyl-1H-imidazo[4,5-f][1,10]phenanthroline ( 1 ), 2-(2-naphyl)-1H-imidazo[4,5-f]phenanthroline ( 2 ), and 2-(2-anthryl)-1H-imidazo[4,5-f]phenanthroline ( 3 ) have been synthesized and characterized. Effects of aryl subsistiuents (phenyl, naphthyl, and anthryl) on the photophysical properties of these ligands in solution have been studied. Ligand 1 exhibit the main absorption band at 283 nm with the shoulder bands at 300–350 nm and these bands are assigned as the typical π→π* (imPhen) state (imPhen = 1H-imidazo[4,5-f][1,10]phenanthroline). A similar absorption spectrum was also observed in the case of 2, in which the charge transfer (CT) state should be considered. 3 shows the slightly different absorption properties compared to that of 1 and 2 . The highest-lying absorption band at 257 nm is assigned as a mixed π→π* (imPhen) /π→π* (Anth) (Anth = anthracene) state. Additionally, the characteristic absorption band of anthryl group with three vibronic bands at 352, 367, and 386 nm also observed in the visible region range from 340 to 400 nm. 1 shows the typical ligand-centered 1 π→π* emission, while 2 and 3 emit from the mixed 1 π→π*/CT states. Density functional theory (DFT) and time-dependent density functional theory (TDDFT) were employed to rationalize the photophysical properties of these ligands studied. The theoretical data confirm the assignment of the experimental absorption spectra and the nature of the emitting states. [ABSTRACT FROM AUTHOR]

• Three-coordinate copper(I) complexes bearing POP and monodentate substituted-quinoline ligands were synthesized and characterized. • The electron-donating/withdrawing groups including methoxyphenyl and trifluoromethylphenyl groups were inserted into the complexes. • Cu(I) complexes exhibited yellow-green emissions at 542-558 nm with longer excited-state lifetimes of 179–487 µs. • The photophysical properties were explained by DFT and TDDFT calculations. The three-coordinate Cu(I) complexes [Cu(POP)(X)]PF 6 , X = quinoline (P1), 2-(4-methoxyphenyl)quinoline (P2), 2-(4-(trifluoromethyl)phenyl)quinoline (P3), POP = bis[(2-diphenylphosphino)phenyl] ether were synthesized and characterized. The photophysical properties of these Cu(I) complexes were tuned by the addition of organic groups including methoxyphenyl and trifluoromethylphenyl groups into the quinoline ligand. The resulting complexes exhibit the metal-to-ligand charge transfer (MLCT) band in the lower energy. The emissions for all the complexes in solid state are in the range of 542–558 nm with higher quantum yields of 11.4–14.2% and long-lived excited lifetimes of 179–481 µs at room temperature. The photophysical properties were further explained by DFT and TDDFT methods. [Display omitted] [ABSTRACT FROM AUTHOR]

• Schiff base copper (I) complexes bearing the bulky adamantyl moiety were synthesized and characterized. • The electron-donating/withdrawing groups including –OCH 3 and –CF 3 were inserted into the complexes. • Cu(I) omplexes exhibited organe-red emissions at 611–619 nm with shorter excited-state lifetimes of 5.55–7.53 μs. • The origin of the emission is attributed the 3MLCT/3LLCT/3π-π* state supported by the TDDFT calculations. Herein, the three novel copper (I) complexes bearing Schiff base ligands of the types [Cu(Phen-PyMethylene-Adam-Amine)(POP)]PF6 (P1), [Cu(Methoxyl-Phen-PyMethylene-Adam-Amine)(POP)]PF6 (P2), and [Cu(TriflMethyl-Phen-PyMethylene-Adam-Amine)(POP)]PF6 (P3) (Phen-PyMethylene-Adam-Amine = ((5-phenylpyridin-2-yl)methylene)adamantan-1-amie, Methoxyl-Phen-PyMethylene-Adam-Amine = ((5-(4-methoxyphenyl)pyridin-2-yl)methylene)adamantan-1-amine, TriflMethyl-Phen-PyMethylene-Adam-Amine = ((5-(4-(trifluoromethyl)phenyl)pyridin-2-yl)methylene)adamantan-1-amine, POP=bis[2- diphenylphosphino ]-phenyl)ether) have been prepared and investigated. Incorporation of the bulky adamantyl group into the complexes can enhance the stability of the complexes. The different electron-donating/withdrawing groups such as –H, –OCH 3 , and –CF 3 substituents were functionalized onto the pyridine ring part of Schiff base ligands to tune the emission behavior of the resulting Schiff base Cu(I) complexes. All complexes exhibit the lowest energy metal-to-ligand charge transfer (MLCT) characters in 400–450 nm region showing a slight blue-shift of the absorption wavelengths in the order P3 > P1 > P2. Organe-red emissions in the region of 611-619 nm with photoluminescence quantum yields (PLQY) of 1.0–1.3% can be observed in the solid state. Additionally, the photophysical properties are also investigated theoretically using density functional theory (DFT) and time dependent DFT. [Display omitted] [ABSTRACT FROM AUTHOR]

• The article we are going to contribute has the following highlights: • Two rare earth metal organic frameworks were synthesized by solvothermal method using zwitterionic 1,3-Bis(1-carboxylatoethyl)imidazolium bromide as ligand. • Complex 2 of Gd(C 9 H 11 N 2 O 4)(C 2 O 4)(H 2 O) (C 9 H 11 N 2 O 4 2‒ = 1,3-Bis(1-carboxylatoethyl) imidazolium ion, C 2 O 4 2- = oxalate) shows antiferromagnetic interactions in the temperature range 2−300 K. Good water-solubility, integrity and stability of 2 significantly different from common complexes grant it great potential in bio-related applications. Two rare earth coordination polymers named {[La 6 (C 9 H 11 N 2 O 4) 11 (H 2 O) 2 (OH) 2 ]⋅Br 5 } n (1) and [Gd(C 9 H 11 N 2 O 4)(C 2 O 4)(H 2 O)] n (2) (C 9 H 11 N 2 O 4 2‒ = 1,3-bis(1-carboxylatoethyl) imidazolium ion, C 2 O 4 2- = oxalate) were solvothermally synthesized using zwitterionic 1,3-bis(1-carboxylatoethyl)imidazolium bromide as ligand. 1 and 2 were both structurally characterized by single crystal X-ray diffraction, and their thermodynamic properties and magnetic properties of 2 were studied. In the 3D structure of 1 , La3+ ions are all ten-coordinated and exhibit three different coordination environments. This 3D structure of 1 is formed by La−O coordination bonds with Br− located in the cavities through H-bond and electrostatic attraction. Different from 1 , all Gd3+ ions in 2 have the same eight-coordinated environment. These two coordination polymers both have good thermostability until 323 °C for 1 and 375 °C for 2 , and then decompose giving rise to La 2 O 3 and Gd 2 O 3 , respectively. The magnetic behaviors of 2 are measured in the temperature range 2–300 K. [Display omitted] [ABSTRACT FROM AUTHOR]

• Schiff base-type copper(I) complexes were synthesized and characterized. • Triphenylamine group was employed to construct copper(I) complexes with high light absorption abilities. • The photophysical properties of complexes including phenyl, naphthyl and adamantanyl groups were investigated.. • DFT/TDDFT methods were employed to rationalize the photophysical properties. The three Schiff base-type Cu(I) complexes [Cu(POP)(N^N)]PF 6 , N^ N = N ,N-diphenyl-4-(6-((phenylimino)methyl)pyridin-3-yl)aniline (P1), N-((5-(4-(diphenylamino)phenyl)pyridin-2-yl)methylene)naphthalen-2-amine (P2), N-((5-(4-(diphenylamino)phenyl)pyridin-2-yl)methylene)adamantan-1-amine (P3), were prepared and characterized. The photophysical properties of these Cu(I) complexes is tuned by the addition of different substituents such as phenyl, naphthyl and adamantanyl groups into the backbone of Schiff base ligand. The resulting complexes exhibit high absorption ability in the visible region with molar extinction coefficients of up to 3 7400 M−1 cm−1. The emissions in CH 2 Cl 2 solution are in the range of 551–552 nm with lower quantum yields of 1.1–2.0% and short-lived excited lifetimes of 2.78–3.09 ns for all the complexes at room temperature. The photophysical properties were further explained by DFT and TDDFT methods. [Display omitted] [ABSTRACT FROM AUTHOR]