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The porphyrin handbook - Kadish K.M.

Kadish K.M. The porphyrin handbook - Academic press, 2000. - 368 p.
Download (direct link): kadishsmishgulilard2000.djvu
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The SHG remained unchanged to 180C.
Li etal.49 looked at the SHG properties of self-assembled monolayer
thin films of tetra-para-pyridylporphyrin [H2(TPyP)] and some derivatives
on fused quartz and silicon surfaces. By covalently bonding the TPyP
molecules to an alkyl- or phenyl-siloxy group, the centrosymmetric
Table 6. INDO/S Hamiltonian and Singles-Only Cl Calculated ji Values for
Pyrrole-Substituted Triphenyl Porphyrins

m2
No. X Y Z fix (10-30 esu) /^(-48 esu)
la CH=CH N CH 64.02 687.76
lb CH=CH N N 78.98 1349.74
lc CH CH 75.55 908.32
Id N CH 87.68 942.84
le N N 85.02 1222.98
If s CH CH 46.42 838.73
lg s N CH 59.44 1042.33
lh s N N 69.35 1352.37
H NH CH CH 80.43 839.91
U NH N CH 89.19 742.33
lk NH N N 93.14 1071.33
N11,
zXz
II 1
"r"
NO,,
No. X Y z M10 30 esu) /!/;"( 10-48 esu)
2a c=c C=CH CH 146.75 2633.8
2b N=N CH=CH CH 193.96 5454.7
2c N=N NH N 245.49 5892.8
58
Chou et al.
Table 6. (continued)
Z'^Z
II I
Z^2
A
No. D A X Y
z /?, (10 30 esu)* M/?x(10-48 esu)
3a NH, NO, c=c
CH=CH CH 157.22 2492.4
3b NIL NO, N=N
CH=CH CH 218.76 4625.4
3c NH, NO, N=N
NH N 345.75 3616.78
3d NO, NH, c=c
CH=CH CH 98.86 2390.65
3e NO, NH, N=N
CH=CH CH 352.69 6435.4
3f NO, NH, N=N
NH N 305.22 8897.73
Source: Albert. I. D. L.: Marks. T. J.; Ratner. M. A. Chem. Mater. 1998,
10. 753.
nature of the porphyrin is nullified. The SHG response at 532 nm was
observed (xzzz ~ 2 x 10 -8 esu). This relatively large value was
attributed to a completely delocalized -electron system in the in the
porphyrin monolayer.
2. Third-Order NLO Systems
As with phthalocyanines, the third-order nonlinear optical
susceptibility, y_,]\ of porphyrins can be manipulated by chemical
substitution. The third-order NLO properties of several
tetraphenylporphyrin compounds were first reported by Meloney et al.50
The x<3) was measured by the degenerate four-wave mixing (DFWM) technique
from
toluene solutions of free-base, zinc and cobalt-containing TPPs. The
effective /13' values of these materials were estimated from the
thermally induced refractive index changes. All porphyrin derivatives
showed x<31 values on the order of 10 ~ 11 esu. Sakaguchi et a/.51 also
used DFWM for determining the /(3) values of cobalt, nickel, zinc, copper
and oxovanadium complexes of 5,10,15,20-tetrakis(4-n-penta-
decylphenyl)porphyrins, H2[T(4-n-C|,H3|)PP]. The measurements were made
in a benzene solution with concentrations of 0.02-0.05%. The %<3) values
were found to be in the range of 10 ^ " esu, however, these values are
influenced by concentration. The Cu[T(4-n-C|5H3|)PP] having a 0.05%
weight dissolved in benzene showed %(3) of 1.8 x 10 ~ 11 esu whereas the
Ni[T(4-n-C] SH3, )PP] accorded /131 of 10 10 esu at a concentration of
0.5g/L. The %<3) values did not exhibit any significant effect of the
metal atom.
Rao et al.52 measured /(3) values of a series of metal containing
tetrabenzoporphyrin derivatives in tetrahydro-furan employing the DFWM
technique at 532 nm. The chemical structures of these porphyrins and
their abbreviated names are listed below (Figure 31, Table 1). These
benzoporphyrins were substituted at the 5,10,15,20-positions with a
variety of functional groups such as m-fluorophenyl, /7-methoxyphenyl
and/;-methylphenyl. Values as high as 2.8 x 10 " 8 esu for (3) were
observed for zinc
5.10.15.20-tetrakis(/?-dimethylaminophenyl)tetrabenzopor-phyrin,
H2(TMAPTBP). In particular, large /'3| values were recorded for
benzoporphyrins containing electron donating
5.10.15.20-phenyl groups. Guha
et al.53, evaluated imaginary and real parts of /131 for the zinc
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