Structure-Optical Property Relationships of Porphyrins

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Mat. Res. Soc. Symp. Proc. Vol. 479 ©1997 Materials Research Society

TABLE I PORPHYRINS SYNTHESIZED TO DATE 72 R4

1

,

8

R2

MN

3

6 5 Compound

Metals

I

Free Base, Cd, Co, Cu, Pb, Zn

Na 4 R 1, R 3

Free Base, Cd, Co, Cu, Pb, Zn

R 2, R 4 Si(CH3 )3

Free Base, Cd, Co, Cu, In, Pb, Zn

-

IV

Free Base, Pb, Zn

ci

ci

ci

ci

V

Free Base, Cd, Co, Cu, Pb, Zn H

VI

Free Base

IIa

z.

Si(CH3 )3

C-C

C_

-CH

3

H VII

Free Base, Cd, Co, Cu, Ni, Pb,

Zn

Br Br

VIIIa

Free Base, Cd, Co, Cu, Pb, Zn

IXb Free Base H H xc Free Base, Zn, Pb H H aBr atoms at positions 1-8. bpositions 1,3,6,7 = CH 3 ; positions 4,5 = CH 2 CH 2 COOCH 3 ; positions 2,8 = H CPositions 1,3,6,7 = CH 3 ; positions 4,5 = CH 2 CH 2 COOCH 3 ; positions 2,8 = Br

314

Si(GH3)3

28

--

----

VII

IX

VI:

--. .. ..........-. .. . ..-----.. . .. . .. . .. . .. . ..----. .. . .. . .. . . .. . --------------------------------...

--------. ..... -- .......----...........---

Vill S 20

--- ----

"16 13

14

15

16

17

18

Q Band Energy(10 cmn'

Figure 1. Plot of B 0-0 band transition energies vs. Q 0-0 band transition energies for free base porphyrins.

""

Slope = 0.97904 ........... ............ ........... I.................................. ----....................... ...................... .-.------22 .5 -.Intercept 6,595 cm-1 r 0.976C Cd22Cu



20.5

20 13.5

.-. .S+ . I. , Pb .... .... ... 14

14.5

I ....- . . ..15.5

15

16

Q Band Energy(10 3 cm"1 )

16.5

Figure 2. Plot of B 0-0 band transition energies vs. Q 0-0 band transition energies for a series of metal derivatives of porphyrin II.

315

16 14 12 B

10 8 B

6

C.-

4 2

C

0

I

. . . I

I

I

I

I

Free Base

Co

.

.

Si(CH 3) .

.

I I

I

Cu

Zn

,

,

Cd

,

,

( I

Pb

Metal

Figure 3. Plot of ratio of oscillator strength of B band to that of Q band as a function of metal for porphyrins I, II and VIII.

1

I

1

I

-

-"

ý

-

1-"""1 1

0.8 V C 0

-

"1

I

'

-"

"I"

CoBrTPP -

-

-

0.6

E C

0.4

Br~TI =

-_

- I.-BrTPPT--=- I

- -

0.2

-- ..

ZnBrTPP" ....

2. .. ..

010-3

10-2

10-

0. .

.. .

10

100

.

.. .

--1

2 - -• ,

102

3

103

Peak Fluence (j/cm2 ) Figure 4. Optical limiting curves for porphyrin VIII metal derivatives. BrTPP is free base porphyrin VIII. Optical limiting curve for C60 included for comparison.

316

Pump-probe Transient Absorption Cross Pol. rU. -,(

I

I

I

I

I

2.20 mJ/cm 2

I

0.6C:

0.5-

0

CD

E

........

-----. -----.. ............. L---------------• ----------.-...... --/------

0.4-

7.05mJ/cm 2

S. ...................... [--------------.. ................................. -.............-

---------... -----......... --..... ..... .......... . .... ........ / ........... !................ . :.......... ----..................

U-

0.3 •-

F_

0.20.1-

mm c at.. . 1.. .....................

Damage occured

. ... -. . ................. ------------------ -ZnBrTPP/Chloroform

lmm cell at 532nm

(A

-2

0

2

4

6

8

10

12

14

Time (ns) Figure 5. Pump-probe data for Zn-VIII at 532 nm.

Table II Excited State Parameters