slide1 n.
Download
Skip this Video
Download Presentation
Steven C. F. Kui, Stephen Sin-Yin Chui, Chi-Ming Che,* and Nianyong Zhu presenter : 戴 如妮

Loading in 2 Seconds...

play fullscreen
1 / 32

Steven C. F. Kui, Stephen Sin-Yin Chui, Chi-Ming Che,* and Nianyong Zhu presenter : 戴 如妮 - PowerPoint PPT Presentation


  • 218 Views
  • Uploaded on

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

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about 'Steven C. F. Kui, Stephen Sin-Yin Chui, Chi-Ming Che,* and Nianyong Zhu presenter : 戴 如妮' - jessenia-kianoush


Download Now An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
slide1

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, 8297-8039

supramolecular coordination chemistry
Supramolecular Coordination Chemistry

Hydrogen bonding

p-p interaction

Metal to ligand binding

van der Waals forces

Holliday, B. J. et. al.Angew. Chem. Int. Ed.2001, 40, 2022-2043.

slide3

C-H … p

p…p

Supramolecular Assembly of Polyhedra

Stang, P. J.; Olenyuk, B. Acc. Chem. Res.; 1997, 30, 502-518

slide4

(C^N^N)Pt(II) Complex Containing a Monoaza-15-Crown-5

Mg

HC^N^N = 4-(4-tolyl)-6-phenyl-2,2'-bipyridine

CH3CN (1.2x10-5M)

Photoinduced Electron Transfer (PET)

Yang, Q. -Z. et. al. Inorg. Chem. 2004, 43, 5195.

organoplatinum crystals for gas triggered switches
Organoplatinum Crystals forGas-Triggered Switches

Koten, G. V. et. al. Nature. 2000, 406, 970-974.

volatile organic compounds vocs

a)

Vapoluminescence

Volatile Organic Compounds ( VOCs )

b)

(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, 16841-16849.

b) William, B. C. et. al. J. Am. Chem. Soc. 2004, 126, 1594-1595.

crystal structure of c n c 2 pt 2 dppm

CHCl3

Crystal Structure of [(C^N^C)2Pt2(μ-dppm)]

anti-

B

[(C^N^C)2Pt2(μ-dppm)]

[(C^N^C)2Pt2(μ-dppm)]

[(C^N^C)2Pt2(μ-dppm)]∙CHCl3

P(1)-Pt(1)-N(1) = 171.2(2)

P(2)-Pt(2)-N(2) = 174.6(3)

P(1)-Pt(1)-N(1) = 170.6(2)

P(2)-Pt(2)-N(2) = 172.4(2)

Che, C.-M. et. al. Organometallics. 2001, 20, 2477-2486.

rourke s method
Rourke’s Method

[(R-C^N^C)Pt(DMSO)]

[(R-C^N^C)Pt(L)]

[(Ph-C^N^C)Pt(PPh3)]

[(R-C^N^C)2Pt2(μ-dppm)]

Rourke, J. P. et. al. Organometallics. 2000, 19, 1355-1364.

simulated 31 p 1 h nmr spectra of 4b in syn and anti
Simulated 31P{1H}NMR Spectra of 4b inSyn- and Anti-

syn-

anti-

Simulated based on AA′XX′ system, 31P NMR (162 MHz,CD2Cl2)

uv vis absorption and solid state emission spectra of 2b 3 and 4b at r t

ligand p*

ligand-ligand transition

s*

metal d

metal-ligand charge transfer

n

metal d

n ligandp

s

ligand-metal charge transfer

metal-metal (d-d) transition

2b ~ excimeric (A-A*)3ππ* excited states4b ~ excimeric 3ππ*excited states

3 ~ intraligant 3ππ*excited states

UV-Vis Absorption and Solid-State Emission Spectra of 2b, 3, and 4b at R. T.

charge transfer

d-d transition

emission spectra of 2b 4b

Vibronic coupling – interaction between electronic and vibrational

modes, increase intensity

Emission Spectra of 2b & 4b

a)

b)

2b

in the solid state at 77 K

in 2-MeTHF at 77 K

4b

in the solid state at 77 K

in 2-MeTHF at 77 K

emission spectra of 3
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

the emission spectra of 4b at various temperature
The Emission Spectra of 4b at Various Temperature

523 nm

566 nm

non - emission

Emission spectra of 4b in 2-MeTHF solution at 103-263 K

  • the molecular motion of the flexible Pt-P-CH2-P-Pt unit
  • (ii) the presence of a low-lying non-emissive d-d excited state
solid 4a under ambient light and under uv light irradiation
Solid 4a under Ambient Light and under UV Light Irradiation

a)

b)

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 CHCl3 vapor.

vapoluminescent behavior of 4a
Vapoluminescent Behavior of 4a

Ivoc is the emission intensity

of desolvated 4a upon exposure to VOC under

saturation conditions

Idesolvateis the emission

intensity of desovated 4a

the crystal structure for 2a
The Crystal Structure for 2a

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

the crystal structures for 2b 2c
The Crystal Structures for 2b & 2c

2b.CHCl3

2c.CH2Cl2

Perspective view of 2b·CHCl3 & 2c·CH2Cl2with the omission of hydrogen atoms.

porous molecular structure of 4a 6chcl 3 c 5 h 12
Porous Molecular Structure of 4a·6CHCl3·C5H12

syn-

anti-

solvent channels

6.5 Å X4.3 Å

the structures of 4c 4d

solvent channels

7.4 Å X2.8 Å

solvent channels

4.6 Å X2.0Å

The Structures of 4c & 4d

syn -4c·3CH2Cl2

anti -4d·2CHCl3

compared with pxrd of structures of solvated and desolvated 4a

loss of solvent

2q = 5.297o

Volume = 7374 Å3

2q = 5.877o

Volume = 6188 Å3

(hkl)

2q

q

Compared with PXRD of Structures of Solvated and Desolvated 4a

Ewald Sphere

http://ruppweb.dyndns.org/xray/tutorial/ewald.htm

packing diagram of desolvated 4a

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

conclusions
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 theemission properties of squar planar Pt(II)complexes is the basic operating principle behind their application as molecular VOC sensory materials.
excimers excited state dimers
Excimers ~~ excited-state dimers

excimeric (A-A*)3ππ*

http://en.wikipedia.org/wiki/Excimer

vibronic coupling
Vibronic Coupling
  • When there is an atom common to the two vibrations.
  • Bending vibrations requires a common bond between the vibrating groups.
  • The stretching bond forms one side of the angle that varies in the bending vibration.
  • The coupled groups have individual energies that are approximately equal.
slide30
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

2q

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).