RESUMO
Two thiacalix[4]arene-protected silver(I) alkynyl nanoclusters, [Na2(H2O)2][Ag9(TC4A)(tBuCîC)4(CH3OH)2(SbF6)0.5(OH)2.5]·3.5H2O·CH3OH (1, abbreviated as Ag9) and [Ag9(TC4A)(tBuCîC)4(CF3COO)]2·4CH3OH (2, abbreviated as Ag18), were synthesized by the reaction of [tBuCîCAg]n, p-tert-butylthiacalix[4]arene (H4TC4A), NaBH4, and AgSbF6 or CF3COOAg in the mixed solvent of methanol-trichloromethane-toluene under solvothermal conditions, respectively. Driven by SbF6- and CF3COO- with different coordination properties, the structural unit [Ag9(TC4A)(tBuCîC)4]+ in both the compounds migrated in different modes, accompanied by distinct Agâ¯Ag distances. Ag9 and Ag18 exhibit similar UV-Vis absorption and diffuse reflection spectra along with contrary tendency between photocurrent responses and solid-state fluorescence. The solution stability of Ag9 and Ag18 was demonstrated by 1H NMR and MALDI-TOF mass spectrometry. The fluorescence responses of Ag9 and Ag18 towards different organic molecules were also investigated, which indicated that the polarity of solvent has a certain effect on the emission intensities of Ag9 and Ag18. This study provides a positive guide for the controlled synthesis and further study of the structure-activity relationship of thiacalix[4]arene-protected silver alkynyl nanoclusters.
RESUMO
Structural transformation is important for the study of silver cluster compounds, in which controlled synthesis of their shapes and sizes via anion template-driven is one key scientific question. In this work, the CO3 2- anion templates were captured by the [t BuC≡CAg]n system under the stimulation induced by carboxylate ligand CF3 COO- /PhCOO- , and two silver alkynyl clusters [(CO3 2- )@Ag21 (t BuC≡C)16 (CF3 COO)3 (H2 O)]â DMFâ 2CH2 Cl2 (1) and [(CO3 2- )2 @Ag24 (t BuC≡C)16 (PhCOO)4 ]â CH3 OHâ 4DMF (2) have been successfully isolated and charactered. With the increase of the number of CO3 2- templates from single to double, the outer silver atoms from twenty-one to twenty-four, accompanied by the growth of the cluster skeleton from 9.8â Å ×6.9â Å of the (CO3 2- )@Ag21 unit to 10.5â Å ×7.3â Å of the (CO3 2- )2 @Ag24 unit. In addition, the syntheses, structures, photocurrent responses, cyclic voltammetry characteristics, luminescence, and photodegradation of compounds 1 and 2 have been studied.
RESUMO
Compound [Ag44 (W10 O32 )(St Bu)24 (CF3 COO)8 ](CF3 COO)6 â 6H2 O (1) was synthesized through a one-pot method. This is the first case of isolating a new silver thiolate cluster containing a [W10 O32 ]6- template which transforms from WO4 2- polyoxoanion through a self-assembly process. The anionic nature of the reduced [W10 O32 ]6- template and the effective silver-oxygen interaction contribute to the formation of the Ag44 nanowheel in 1. The luminescence, photocatalytic activity and electrochemistry properties of 1 were studied.
Assuntos
Luminescência , Prata , Ânions , Prata/químicaRESUMO
The chiral dodecanuclear palladium(II) thio cluster LaPd12(C3H5NO2S)3(C3H6NO2S)21 (1) was prepared by reacting l-cysteine (l-Cys) with PdCl2 and La2O3 in aqueous solution under carefully controlled conditions. Compound 1 was structurally characterized by single-crystal XRD, TGA, IR, UV-vis, (13)C NMR, and CD spectroscopy. Insight into the dimerization process of 1 was obtained by ESI-MS and DFT calculations.
RESUMO
Seven polyoxopalladate compounds, [Pd(15)(SeO(3))(10)(µ(3)-O)(10)](10-), with Na(+) (1) and K(+) (2) as counterions, and Na(6)[M(II){Pd(12)(SeO(3))(8)(µ(4)-O)(8)}]·nH(2)O (M = Co (3), Zn (4), Ni (5), Cu (6), Mn (7); n = 7-9), have been prepared and characterized by SXRD, FT-IR, UV-vis, EA, TGA, and ESI-MS. These compounds comprise two distinct cluster configurations, {Pd(15)} and {M(II)Pd(12)}, which reveals the possibility of obtaining desired noble metal clusters with a certain nuclearity by using different cations as potential structural directing or template agents in synthesis. All compounds showed apparent absorptions in the visible light region, while 3 and 7 were found to show paramagnetic behavior typical of mononuclear Co(II) and Mn(II) complexes with zero-field splitting.