A Chemically Functionalizable Nanoporous Material [Cu 3 (TMA) 2 (H 2 O) 3 ] n
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Feng P., Bu X., Tolbert S. H., Stucky G. D., J. Am. Chem. Soc. 119, 24987 (1997).
Blake A. J., et al., ibid. 1997, 1005 (1997);
; A. J. Blake et al. ibid. p. 2027; C. J. Kepert and M. J. Rosseinsky ibid. 1998 31 (1998).
Pech R., Pickardt J., Acta Crystallogr. C44, 992 (1988).
Chui S. S.-Y., Williams I. D., ibid. C55, 194 (1999).
Crystals of [Mn(TMA-H 2 ) 2 (H 2 O) 4 ] were formed by layer diffusion of ethanolic [TMA-H 3 ] into aqueous Mn(OAc) 2 at RT. The monoclinic crystal system data are as follows: unit cell edges are a = 5.178(2) Å b = 13.127(3) Å and c = 15.142(3) Å; interaxial angle β = 97.74(2)°; and cell volume V = 1019(1) Å 3 .
In a typical synthesis 1.8 mM of cupric nitrate trihydrate was heated with 1.0 mM of trimesic acid (TMA-H 3 ) in 12 ml of 50:50 H 2 O:EtOH (EtOH ethyl alcohol) at 180°C for 12 hours in a Teflon-lined 23-ml Parr pressure vessel. This gave turquoise crystals up to dimensions of 80 μm in ∼60% yield along with Cu metal and Cu 2 O. Single-crystal x-ray analysis of the turquoise crystals (HKUST-1) was carried out with a Siemens diffractometer that was equipped with a SMART charge-coupled device.
Crystal data for HKUST-1 were measured as follows: C 18 H 12 O 15 Cu 3 relative molecular mass M r = 658.9 cubic crystal system space group Fm - 3m a = 26.343(5) Å V = 18 280(7) Å 3 formula units per cell Z = 16 density D x = 0.96 g cm –3 conventional discrepancy index R = 5.99 and weighted wR2 = 16.78; for 43 least-squares parameters and 853 reflections diffraction angle 2Θmax = 50°. The structure was refined with SHELXL. A full description of the x-ray analysis is available at www.sciencemag.org/feature/data/986116.shl. The coordinates are on deposit with the Cambridge Structural Database deposit number 112954.
D. W. Breck Zeolite Molecular Sieves (Kreiger Malabar FL 1974) p. 48; ibid. p. 625. The BET data are available at www.sciencemag.org/feature/data/986116.shl.
Lattice expansion occurred in a family of Cu polymers containing N N′ donor bridges [
; S. Kitagawa paper presented at the 1st International Conference on Inorganic Materials Versailles 16 to 19 September 1998].
TGA results for HKUST-1 gave weight loss Δ w = –28.2% from 25° to 120°C (–13 H 2 O) thermal stability from 120°C to 250°C and Δ w = –25.4% from 250° to 400°C (–CO 2 and others). Further heating to 800°C resulted in a mixture of CuO and glassy C as final products. TGA curves are available at www.sciencemag.org/feature/data/986116.shl.
The analytical and calculated (in parentheses) data for [Cu 3 (TMA) 2 (py) 3 ]·0.5(py)·2H 2 O are as follows: C 43.54% (46.48%); H 3.54% (3.01%); and N 5.52% (5.30%). TGA showed Δ w = –3.9% from 25° to 120°C and Δ w = –54.2% from 120° to 400°C (–py –CO 2 and others).
A 2D network polymer [Cu 3 (TMA) 2 (py) 9 ]·3(py)·3H 2 O (space group R-3c a = 19.142(5) Å c = 42.64(1) Å and V = 13 532 Å 3 ) was formed with large 48-membered rings of six individual Cu atoms and six TMA groups.
Analysis for the DMF product gave the best formulation as [Cu 3 (TMA) 2 (H 2 O) 3 ]·2.5(DMF)·2.5(H 2 O) on the basis of combined chemical and thermal gravimetric analyses. The analytical and calculated (in parentheses) data are as follows: C 34.6% (34.5%); H 3.42% (3.89%); N 4.01% (3.95%); Δ w = –11.4% from 25° to 120°C (H 2 O loss); and Δ w = –48.6% from 150° to 400°C (DMF and CO 2 loss). Variable-temperature single-crystal studies of the DMSO derivative showed no bound DMSO at RT; heating up to 200°C produced intensity changes due to solvent loss (reflection 222 increases in intensity and reflection 400 decreases). Cooling to RT resulted in a general reversal of these trends.
Anhydrous [Er(TMA)] was synthesized hydrothermally at 180°C in a manner similar to the synthesis of HKUST-1; TGA under N 2 produced Δ w = < –1% from 25° to 500°C and Δ w = –45.7% from 500° to 650°C corresponding to decarboxylation.
We are grateful to the Research Grants Council of Hong Kong (RGC grants 6148-97P and 6061-98P) and the Advanced Materials Research Institute (AMRI-HKUST) for financial support and to J. Zheng and A. Siu for technical assistance.