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Brett D. Chandler, David T. Cramb,* and George K. H. Shimizu*

Microporous Metal - Organic Frameworks Formed in a Stepwise Manner from Luminescent Building Blocks. Brett D. Chandler, David T. Cramb,* and George K. H. Shimizu*. J. Am. Chem. Soc. 2006 , 128 , 10403-10412. Lanthanide Ions Are Employed Photonic Applications.

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Brett D. Chandler, David T. Cramb,* and George K. H. Shimizu*

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  1. Microporous Metal-Organic Frameworks Formed in a Stepwise Manner from Luminescent Building Blocks Brett D. Chandler, David T. Cramb,* and George K. H. Shimizu* J. Am. Chem. Soc. 2006, 128, 10403-10412

  2. Lanthanide Ions Are Employed Photonic Applications Angew. Chem., Int. Ed. 1998, 37, 3085-3103

  3. Several Properties of Lanthanides 1.Different Ln ions emit spans a wide spectrum from infrared radiation to blue light. 2. 4f orbitals are shielded by the 5s and 5p orbitals leading to desired sharp emission lines.

  4. Antenna Effect This occurs from direct excitation of the ligand to a singlet state followed by an intersystem crossing to a triplet state. J. Chem. Soc., Dalton Trans. 1985, 2247.

  5. Exchanging Ln Ions for Intrachannel Cations in Zeolites zeolite Y (Na7(NH4)49Y; Si/AI = 2.5). + EuCl3 Ligand exchange porous J. Am. Chem. Soc. 1988, 110, 5709-5714.

  6. Ln Silicates with the Ln Ion Hydrothermal conditions AV-9：Aveiro microporous solid no. 9 AV-9 = Na4K2X2Si16O38‧10H2O J. Am. Chem. Soc. 2001, 123, 5735-5742.

  7. Metal-Organic Frameworks (MOFs) of Ln-Containing Solids Eu(NO3)3‧6H2O + HO2C-C10H14-CO2H Tb3++1,4-benzenedicarboxylic acid (H2-BDC) J. Mater. Chem. 2004, 14, 642-645 J. Am. Chem. Soc. 1999, 121, 1651-1657

  8. Antenna Ligand J. Lumin. 2000, 86, 137-146.

  9. Possible Bonding Modes for Sulfonate Ligand + Ba2+ MOF Cryst. Growth Des. 2005, 5, 807-812

  10. Target Antenna Ligand Antenna ligand + sulfonate groups L 4,4’-disulfo-2,2’-bipyridine N,N’-dioxide

  11. To Design the MOFs M : L = 1 : 4 Densed Structure increase M/L ratio M : L = 1 : 3

  12. A Stepwise Approach to the Formation of Metal-Organic Frameworks

  13. General Synthesis of Compound 2

  14. The Local Environment of the Ln Ion 12.49 × 9.84 Å2

  15. Sulfonate Groups Bonding Mode of Ba1 Ion

  16. Ba1 Center Cross-Link of [EuL3(H2O)2]3-

  17. Sulfonate Groups Bonding Mode of Ba2 Ion

  18. Ba2 Center Cross-Link of [EuL3(H2O)2]3-

  19. The Cl- Ions Occupying the Complex’s Channels • O(i) ... Cl =3.133 Å • Cl ...C(ii)=3.60(1)-3.85(1) Å, • Cl ... H-C(ii)= 166.2(3)°-178.8(3)° • H2O on the Eu center • C is -carbons of pyridine ring

  20. The TGA Analysis 105 oC loss 13.29% 320 oC No weight loss

  21. Dehydration of Compound 2 under Heat heat crystal amorphous

  22. Reversible Water Vapor Sorption by Compound 2 391.7 min, 96.85% 196.3 min, 97.06% 200.1 min, 99.73% 136.2 min, 86.79% 138.8 min, 86.29%

  23. CO2 and N2 Adsorption Experiments ? ?

  24. Carbon Dioxide Sorption Isotherm for Compound 2 For CO2 : A Dubinin-Radushkevich (DR) analysis gave a surface area of 718 m2/g, an average pore width of 6.2 Å, and a micropore volume of 0.25 mL/g. CO2 sorption experiment was repeated at -42 °C using a dry ice/acetonitrile bath and gave a DR surface area of 210 m2/g.

  25. High Activation Barrier for N2 Sorption For N2 : DR surface 15 m2/gm 1.The presence of a narrow micropore 2.The lower temperature employed for the N2 analysis (77 K) 3.The slightly larger diameter of N2 (3.64Å)versus CO2 (3.30 Å) 4.The topology of the pore structure (one dimensional)

  26. Antenna Ligand Emission band with a maximum appearing at 473 nm. The excitation spectrum shows two main peaks, 325 nm and 395 nm

  27. Energy Level Diagram for the Lanthanides

  28. Phosphorescence Emission Spectrum for the Gd Compound 3 S0

  29. The PhosphorescenceSpectrum of the Eu Compound 2 lifetime 243 s 5D0 → 7F1 is the second most intense transition; 5D0 → 7F2, is consists of an intense band with two weak shoulders. 5D0 →7F3 transition is consists of a less intense broad peak with a small shoulder 5D0 → 7F4 transition is comprised of two well- defined peaks.

  30. The Spectrum of the Tb Compound 4 lifetime:95 s 5D4 → 7F6 consists of an intense peak with a shoulder. 5D4 → 7F5 consists of a single intense peak with a second shoulder. 5D4 → 7F4 and 5D4→7F2 transitions consist of two peaks of equal intensity. 5D4 → 7F3 transition consist a weak shoulder followed by a second intense peak 5D4 → 7F1 and 5D4 → 7F0 transitions are single peakswith weak but measurable intensities.

  31. Radiationless Deexcitation Scheme for Tb( III ) J. Am. Chem. Soc. 1979, 101, 334-340.

  32. The Spectrum of the Sm and Dy Compounds 1&5 lifetime:6 s lifetime:5 s

  33. To Relate the Observed Surface Area to the Single Crystal Structure Connolly surfaces were calculated for compound 2 in two scenarios, first with the noncoordinated water molecules occupying the channels removed and then with both free and coordinated water molecules removed. noncoordinated water removed: 695 m2/gm free and coordinated water molecules removed: 963m2/gm measured surface area : 718 m2/gm

  34. Comparing Luminescent Property of Eu Compound 2 Hydrated and Dehydrated Forms the Ba sulfonate solids was observed typically that, upon loss of coordinated water from the Ba coordination sphere, the solid shifts structure to optimally arrange the remaining sulfonate O donor atoms about the metal ion. it was not expected that Eu complex 2 5D0→7F2: only a single peak 5D0→ 7F4: a small but noticeable shift of the higher frequency peak by 3 nm to a longer wavelength. lifetime:319 s

  35. Conclusions • A series of isostructural lanthanide-containing metal-organic frameworks which demonstrate permanent microporosity but also incorporate predictable photophysical properties. 2. A DR surface area of 718 m2/g for the dehydrated form of compound 2 was measured by CO2 sorption, the rigid building block enabling the formation of this porous material. 3. Luminescence spectroscopy was also employed as a diagnostic tool to gain additional insight to the nature of the amorphous microporous state.

  36. Summary of Crystallographic Data for Compounds 1, 2, 3, 4, and 5

  37. Term Symbol 1. The ground term (term of lowest energy) has the highest spin multiplicity. 2. If two or more terms share the maximum spin multiplicity, the ground term is the one having the highest value of L. 3. For subshell that are less than half-filled, the sate having the lowest J value has lowest energy.

  38. Eu3+:Xe4f6 L:3 S:1/2×6=3 2S+1=7 因為未多於半滿,所以J要較小→Ｌ-S=0 3 2 1 0 -1 -2 -3 Ground state term symbol:7F0

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