1 Structures, Photoluminescence, and Reversible Vapoluminescence Properties of Neutral Platinum(II) Complexes Containing Extended π- Conjugated Cyclometalated Ligands Steven C. F. Kui, Stephen Sin-Yin Chui, Chi-Ming Che,* and Nianyong Zhu presenter : 戴如妮 J. Am. Chem. Soc. 2006, 128,

2 Holliday, B. J. et. al. Angew. Chem. Int. Ed. 2001, 40, Supramolecular Coordination Chemistry Hydrogen bonding  -  interaction Metal to ligand binding van der Waals forces

3 Stang, P. J.; Olenyuk, B. Acc. Chem. Res.; 1997, 30, Supramolecular Assembly of Polyhedra C-H …   … 

4 HC^N^N = 4-(4-tolyl)-6-phenyl-2,2'-bipyridine Yang, Q. -Z. et. al. Inorg. Chem. 2004, 43, CH 3 CN (1.2x10 -5 M) Mg (C^N^N)Pt(II) Complex Containing a Monoaza-15-Crown-5 Photoinduced Electron Transfer (PET)

5 Organoplatinum Crystals for Gas-Triggered Switches Koten, G. V. et. al. Nature. 2000, 406,

6 (i) the facile reversible change of the molecular structure of the luminophore (ii) alterations in the molecular packing when the analyte molecule enters and exits the crystal structure of the luminescent sensory material. a) Eisenberg, R. et. al. J. Am. Chem. Soc. 2004, 126, b) William, B. C. et. al. J. Am. Chem. Soc. 2004, 126, Volatile Organic Compounds ( VOCs ) Vapoluminescence a)b)

7 Crystal Structure of [(C^N^C) 2 Pt 2 (μ-dppm)] [(C^N^C) 2 Pt 2 (μ-dppm)][(C^N^C) 2 Pt 2 (μ-dppm)]∙CHCl 3 B [(C^N^C) 2 Pt 2 (μ-dppm)] anti- CHCl 3 Che, C.-M. et. al. Organometallics. 2001, 20, P(1)-Pt(1)-N(1) = 170.6(2) P(2)-Pt(2)-N(2) = 172.4(2) P(1)-Pt(1)-N(1) = 171.2(2) P(2)-Pt(2)-N(2) = 174.6(3)

8 [(R-C^N^C) 2 Pt 2 (μ-dppm)] [(R-C^N^C)Pt(DMSO)] [(Ph-C^N^C)Pt(PPh 3 )] Rourke’s Method Rourke, J. P. et. al. Organometallics. 2000, 19, [(R-C^N^C)Pt(L)]

9 Simulated 31 P{ 1 H}NMR Spectra of 4b in Syn- and Anti- syn- anti- Simulated based on AA′XX′ system, 31 P NMR (162 MHz,CD 2 Cl 2 )

10 31 P{ 1 H} NMR Spectrum of 4b in CD 2 Cl 2 Experiment syn- IsotopeNatural abundance/% Spin of nucleus 190 Pt Pt Pt Pt33.81/2 196 Pt Pt7.2

11 The Structures of 2b, 3, 4b

12 2b ~ excimeric (A-A*) 3 ππ* excited states 4b ~ excimeric 3 ππ*excited states 3 ~ intraligant 3 ππ*excited states UV-Vis Absorption and Solid-State Emission Spectra of 2b, 3, and 4b at R. T. charge transfer d-d transition metal-metal (d-d) transition metal-ligand charge transfer ligand-metal charge transfer ligand-ligand transition  * metal d n ligand   ligand  * n metal d

13 Emission Spectra of 2b & 4b Vibronic coupling – interaction between electronic and vibrational modes, increase intensity 2b in the solid state at 77 K in 2-MeTHF at 77 K a) 4b in the solid state at 77 K in 2-MeTHF at 77 K b)

14 Emission Spectra of 3 Emission spectra of 3 in the solid state at room temperature, 77 K, and as a glassy solutionin 2-MeTHF at 77 K

15 The Emission Spectra of 4b at Various Temperature non - emission Emission spectra of 4b in 2-MeTHF solution at K 523 nm 566 nm (i)the molecular motion of the flexible Pt-P-CH 2 -P-Pt unit (ii) the presence of a low-lying non-emissive d-d excited state

16 Solid 4a under Ambient Light and under UV Light Irradiation anbient light UV light Solid 4a under ambient light and under UV light irradiation (350 nm). (a) Orange crystals of 4a upon exposure to air. (b) A reversible vapoluminescence for the desolvated form of 4a within 1 min of being exposed to CHCl 3 vapor. b)a)

17 Vapoluminescent Behavior of 4a I voc is the emission intensity of desolvated 4a upon exposure to VOC under saturation conditions I desolvate is the emission intensity of desovated 4a

18 The Crystal Structure for 2a Perspective view of 2a with omission of hydrogen atoms (left) and the head-to-tail pairs molecular orientation (right).

19 The Crystal Structures for 2b & 2c Perspective view of 2b·CHCl 3 & 2c·CH 2 Cl 2 with the omission of hydrogen atoms. 2b. CHCl 3 2c. CH 2 Cl 2

20 Perspective View of Syn - and Anti - 4a. 6CHCl 3. C 5 H 12 C-H … π C-H(solvent) … π C-H … X

21 solvent channels 6.5 Å X 4.3 Å Porous Molecular Structure of 4a·6CHCl 3 ·C 5 H 12 syn- anti-

22 The Structures of 4c & 4d solvent channels 7.4 Å X 2.8 Å solvent channels 4.6 Å X 2.0 Å syn - 4c·3CH 2 Cl 2 anti - 4d·2CHCl 3

23 (hkl)   Compared with PXRD of Structures of Solvated and Desolvated 4a Ewald Sphere loss of solvent  = o Volume = 6188 Å 3  = o Volume = 7374 Å 3

24 layer of syn-molecules layer of anti-molecules layer of syn-molecules layer of anti-molecules layer of syn-molecules Packing Diagram of Desolvated 4a Molecular packing within desolvated 4a viewed from the c-axis

25 The Vapoluminescent Properties for Solvated & Desolvated 4a ΔG = ΔH –T. ΔS loss of solvent

26 Conclusions Mononuclear and dinuclear cyclometalated [(R-C^N^C)Pt-L] complexes were prepared and structurally characterized. Accessible solvent channels and the presence of weak and reversible non-covalent C-H … π, π … π,C-H … X, and X … X interactions account for the vapoluminescent behavior of 4a. The sensitivity of the emission properties of squar planar Pt(II) complexes is the basic operating principle behind their application as molecular VOC sensory materials.

Excimers ~~ excited-state dimers excimeric (A-A*) 3 ππ*

Vibronic Coupling 1.When there is an atom common to the two vibrations. 2.Bending vibrations requires a common bond between the vibrating groups. 3.The stretching bond forms one side of the angle that varies in the bending vibration. 4.The coupled groups have individual energies that are approximately equal.

Is a short-lived dimeric molecule formed from two species, at least one of which is in an electronic excited state. Excimers are often diatomic and are formed between two atoms or molecules that would not bond if both were in the ground state. The lifetime of an excimer is very short, on the order of nanoseconds.The excimeric emission is red-shifted relative to the emission from the compound monomers

Rietveld Method for the Desolvated Structutre of 4a A graphical plot of the final cycle of Rietveld refinement for the desolvated structutre of 4a (red cross — experimental data point, green line — calculated data, and magenta line — the difference plot between experimental and calculated data points). 22

32 The Seven Crystal Systems