References [1] A. M. Rao, P. Zhou, K-A. Wang, G. T. Hager, J. M. Holden, Y. Wang, W-T. Lee, X-X. Bi,...

References [1] A. M. Rao, P. Zhou, K-A. Wang, G. T. Hager, J. M. Holden, Y. Wang, W-T. Lee, X-X. Bi, P. C. Eklund, D. S. Cornett, M. A. Duncan, I. J. Amster, Science 259, 955 (1993) [2] T. Pusztai, G. Oszlányi, G. Faigel, K. Kamarás, L. Gránásy, S. Pekker, Solid State Commun. 111, 595 (1999) [3] S. Pekker, K. Kamarás, É. Kováts, T. Pusztai, G. Oszlányi, Synthetic Metals 121, 1109 (2001) [4] S. Pekker, É. Kováts, K. Kamarás, T. Pusztai, G. Oszlányi, Synthetic Metals 133-134, 685 (2001) [5] B. Burger, J. Winter, H. Kuzmany, Z. Phys B 101, 227 (1996) [6] O. F. Sankey, D. J. Niklewski, Phys. Rev. B 40, 3979 (1989) Measured and calculated MidIR spectra 500 600 700 800 900 1000 1100 1200 1300 1400 1500 1600 ca lc.re cta n g le ca lc.tria n g le exp.photopolym er exp.dim er A (au.) w avenum b e r (cm -1 ) Photopolymer contains dimer, but other oligomers are present MidIR: assignment of oligomer peaks not conclusive FarIR: fewer lines + no C 60 lines 200 250 300 350 400 450 A (au.) w avenum b e r (cm -1 ) No interball modes 30-200 cm -1 Assignment of photopolymer spectrum with dimer, triangle and rectangle Unassigned peaks: insoluble oligomers + small amount of other trimers and tetramers Measured and calculated FarIR spectra calc. rectangle calc. triangle exp. photopolymer exp. dimer Conclusions (2): 5 cm -1 / cycloadditional bond o interball modes in IR 30-200 cm -1 arIR more informative for assignment than MidIR hotopolymer contains monomer + dimer + triangle + rectangle + other oligomers Measurements • Raman: Renishaw System 1000B microscope + 785nm laser further polymerization avoided • MIR: KBr pellet in Bruker IFS28 • FIR: pure photopolymer pellet @ LHe (4 K) in Bruker IFS 113v Weak lines seen sharper lines Calculations Method: • QMD (quantum molecular dynamics) [6] • local pseudoatomic orbitals, minimal basis • best results: 200-600 cm -1 (FarIR): with 1.05 uniform scaling 2% error • intensities not reliable Molecules: • triangle: most possible (C 60 ) 3 • rectangle: most possible (C 60 ) 4 1420 1430 1440 1450 1460 1470 1480 1490 1500 photopolym er trim er (pre su m a b ly tria ng le ) dimer C 60 In te n sity (a u .) w avenum b er (cm -1 ) Measured A g (2) modes 5 cm -1 / cycloadditional bond Photopolymer contains: C 60 + (C 60 ) 2 + (C 60 ) 3 + higher oligomer Vibrational spectroscopy of C 60 photopolymer G. Klupp*, K. Kamarás, É. Kováts, S. Pekker, T. Pusztai Research Institute for Solid State Physics and Optics, P. O. Box 49, Budapest, H 1525, Hungary, *email: [email protected] Z.-T. Zhu † , V. C. Long ‡ , J. L. Musfeldt § Department of Chemistry, State University of New York at Binghamton, Binghamton, New York 13902 G. B. Adams, J. B. Page Department of Physics and Astronomy, Arizona State University, Tempe, Arizona 85287 Funding: OTKA T034198, OTKA T032613, NATO PST.CLG.977404 Present addresses: † Department of Material Science and Engineering, Cornell University, Ithaca, NY 14853 ‡ Department of Physics and Astronomy, Colby College, Waterville, ME 04901 § Department of Chemistry, University of Tennessee, Knoxville, TN 37996 • Illumination of C 60 + saturated C 60 solution with 2*23W at 320-360K for 40 days C 60 + (C 60 ) 2 + soluble (C 60 ) n>2 + insoluble (C 60 ) n>2 • Repeated extraction with toluene solid photopolymer with less C 60 , (C 60 ) 2 solution of C 60 + (C 60 ) 2 • HPLC separation of the solution (C 60 ) 2 , 99.3% purity • For the preparation of trimer see poster of É. Kováts Preparation Introduction Monomer + Dimer + Trimers (5 possible structures) + Tetramers (17 possible structures) + Higher oligomers (insolubes) Photopolymer = [1], [2], [3] … a = 13.93 – 14.05 Å average ~2 cycloadditional bonds / C 60 unit [2], [4] Different preparation conditions different ratio of the compounds [3], [5]

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Transcript of References [1] A. M. Rao, P. Zhou, K-A. Wang, G. T. Hager, J. M. Holden, Y. Wang, W-T. Lee, X-X. Bi,...

References

[1] A. M. Rao, P. Zhou, K-A. Wang, G. T. Hager, J. M. Holden, Y. Wang, W-T. Lee, X-X. Bi, P. C. Eklund, D. S. Cornett, M. A. Duncan, I. J. Amster, Science 259, 955 (1993)

[2] T. Pusztai, G. Oszlányi, G. Faigel, K. Kamarás, L. Gránásy, S. Pekker, Solid State Commun. 111, 595 (1999)

[3] S. Pekker, K. Kamarás, É. Kováts, T. Pusztai, G. Oszlányi, Synthetic Metals 121, 1109 (2001)

[4] S. Pekker, É. Kováts, K. Kamarás, T. Pusztai, G. Oszlányi, Synthetic Metals 133-134, 685 (2001)

[5] B. Burger, J. Winter, H. Kuzmany, Z. Phys B 101, 227 (1996)

[6] O. F. Sankey, D. J. Niklewski, Phys. Rev. B 40, 3979 (1989)

Measured and calculated MidIR spectra

500 600 700 800 900 1000 1100 1200 1300 1400 1500 1600

calc. rectangle

calc. triangle

exp. photopolymer

exp. dimer

A (

au.)

wavenumber (cm-1)

Photopolymer contains dimer, but other oligomers are present

MidIR: assignment of oligomer peaks not conclusive FarIR: fewer lines + no C60 lines

200 250 300 350 400 450

A (

au.)

wavenumber (cm-1)

No interball modes 30-200 cm-1

Assignment of photopolymer spectrum with dimer, triangle and rectangle

Unassigned peaks: insoluble oligomers + small amount of other trimers and tetramers

Measured and calculated FarIR spectra

calc. rectangle

calc. triangle

exp. photopolymer

exp. dimer

Conclusions

• Ag(2): 5 cm-1/ cycloadditional bond

• No interball modes in IR 30-200 cm-1

• FarIR more informative for assignment than MidIR

• Photopolymer contains monomer + dimer + triangle + rectangle + other oligomers

Measurements

• Raman: Renishaw System 1000B microscope

+ 785nm laser further polymerization avoided

• MIR: KBr pellet in Bruker IFS28

• FIR: pure photopolymer pellet @ LHe (4 K) in Bruker IFS 113v

Weak lines seen sharper lines

Calculations

Method:

• QMD (quantum molecular dynamics) [6]

• local pseudoatomic orbitals, minimal basis

• best results: 200-600 cm-1 (FarIR): with 1.05 uniform scaling 2% error

• intensities not reliable

Molecules:

• triangle: most possible (C60)3

• rectangle: most possible (C60)4

1420 1430 1440 1450 1460 1470 1480 1490 1500

photopolymer

trimer(presumably triangle)

dimer

C60

Inte

nsi

ty (

wavenumber (cm-1)

Measured Ag(2) modes

5 cm-1/ cycloadditional bond

Photopolymer contains: C60 + (C60)2 + (C60)3 + higher oligomers

Vibrational spectroscopy of C60 photopolymer

G. Klupp*, K. Kamarás, É. Kováts, S. Pekker, T. PusztaiResearch Institute for Solid State Physics and Optics, P. O. Box 49, Budapest, H 1525, Hungary, *email: [email protected]

Z.-T. Zhu†, V. C. Long‡, J. L. Musfeldt§

Department of Chemistry, State University of New York at Binghamton, Binghamton, New York 13902

G. B. Adams, J. B. Page Department of Physics and Astronomy, Arizona State University, Tempe, Arizona 85287

Funding: OTKA T034198, OTKA T032613, NATO PST.CLG.977404

Present addresses:† Department of Material Science and Engineering, Cornell University, Ithaca, NY 14853‡ Department of Physics and Astronomy, Colby College, Waterville, ME 04901§ Department of Chemistry, University of Tennessee, Knoxville, TN 37996

• Illumination of C60 + saturated C60 solution with 2*23W at 320-360K for 40 days

C60 + (C60)2 + soluble (C60)n>2 + insoluble (C60)n>2

• Repeated extraction with toluene

solid photopolymer with less C60, (C60)2

solution of C60 + (C60)2

• HPLC separation of the solution

(C60)2, 99.3% purity

• For the preparation of trimer see poster of É. Kováts

Preparation

Introduction

Monomer

+Dimer