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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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tetraphenyl benzoporphyrin species [Zn(TPTBP)] and the /;-methoxy-phenyl
substituted version [Zn(TMOPTBP)] in THF by using picosecond and
nanosecond laser pulses. The imaginary parts of /1,1 and (second
hyperpolarizability)
41 / Porphyrin Materials Chemistry
59
Figure 30. Structure of Peng's zinc porphyrin polyimide system with
pendant organic NLO chromophore.
Figure 31. Structure of Rao's tetrabenzoporphyrin derivatives
Zn(TMAPTBP): M=Zn, X = H, R = p-C6H4-N(CH3)2; Zn(TMTBP): M = Zn, X = H,
R = CH3; Zn(TFPTBP): M = Zn, X = H, R = m-FC6H4; Zn(TMOPTBP): M = Zn, X =
H, R = p-CH30-C6H4; Zn(TMPTBP): M =Zn, X = H, R = p-CH3C6H4; Mg(DMTBP): M
= Mg, X = 8 H and 8-CH3, R = H; Zn(TPTBP): M = Zn, X = H. R = C6H5;
Zn(TFTBP): M = Zn, X = F, R - H; TBP: M - H?, X R. Hi.
-y
1 1 J
N * N -"\
X CH., ^
G
CH, ?H'//
1
"N + H ~ \
A,.-
2CF- /



V
>
v
i
Figure 32. Structure of Hosoda's extended porphyrinic ring
system.
of these two porphyrins at 532 nm were found to be five to ten times
larger than the real parts measured at 1.064 /mi. The Zn(TMOPTBP) showed
an imaginary ^l!) of 9 x 10 13 esu and of 8.0 x 10~?l esu whereas a of
approximately 1.8 x 10 " 11 esu and of 1.6 x 10 ^ esu was observed lor
Zn(TPTBP) at a concentration of 0.46 g/ L.
Nonlinear refractive index values (n:) of 7.8 x 10 1(1 and
9.1 x 10 10 cnr / MW were estimated For Zn(TMOPTBP) and Zn(TPTBP),
respectively.
Hosada et almeasured / ''' of spin-coated films of free-base and
manganese-chloride derivatives of octaethyl-porphyrin (OEP) and N,N ',N
",N '"-tetramethyl-octaetliyl-poq)hyrin(+2) bis(trifluoroacetate) [Me4
(OEP) ^)| by third harmonic generation (TUG) at 1.907 pm to investigate
the effect of increasing ring size on third-order optical nonlinearity
(Figure 32). The x'~" of Mej (OEP) ', with an extended ^-conjugation, was
about live times larger than that of lb(OEP), illustrating the increase
in /(i| as the number of 7i-electrons in the conjugated ring increases.
similar effect is observed in one-dimensional 7T-conjligated polymers
such as polyacetylenes. Mn(OEP)CI showed slightly larger /l3) than
H:(OEP) presumably due to the inclusion of a metal atom.
60
Chou et al.
Figure 33. Structure of Norwood's magnesium octaphenyl-tetraza porphyrin.
Figure 34. Structure of Anderson's 5,10,15,20-diethynylporphyrina-tozinc
polymer.
M^ll 2.7.11
Figure 35. Structure of Bao's porphyrin monomer and polymer.
Norwood and Sounik55 measured %<3) values of magnesium
octaphenyltetrazaporphyrin (Mg(OPTAP)) (Figure 33) as a 5% weight
incorporation in poly(methyl methacrylate) (PMMA). The thin films showed
*0) and X\yy**] values of the order of 1.17x10 " and 3.03 x 10~12
esu, respectively from DFWM at 598 nm. The ratio of xxxxx(S) to Zxyyx<3)
was three, implying that the optical nonlinearity is predominantly
electronic. The Mg(OPTAP) showed a response time of 44 ps.
Anderson et 1.5 synthesized the soluble conjugated porphyrin polymer
of 5,10,15,20-diethylnyl zinc porphyrin (DEtyP)n using Glaser-Hay
coupling (Figure 34). The real and imaginary components of %(3) (-.w\
0,0, w) of these polymers were calculated from the electroabsorption
spectra. The X {-(o; 0,0, (o) on the order of 7.3 x 10 - 8 esu was
obtained at the peak resonance due to resonance enhancement.
Bao and Yu57 synthesized free-base and Zn-metallopor-phyrin-containing
polymers (Figure 35) and measured their X<3> values by DFWM technique at
532 nm. These polymers possess photoconductive and photovoltaic
properties. Notable /ty' values were obtained for the polymeric
materials. The ^,:i) value found for Zn(TPP) was twice as large as the
free-base porphyrin. The x.(?,) values were on the order of 10- 10 esu
for thin films. Polymer solutions showed x0> values of I x 10-12 and 1.9
x 10~ u esu for the Zn and free-base porphyrin polymer materials,
respectively, which was more than two orders of magnitude smaller than
those obtained for thin films. These x<3) values were enhanced due to the
resonant contributions.
Kandasamy et al.5* measured second hyperpolarizabil-ities of six
tetraphenylporphyrin derivatives using the Z-scan technique at 784 nm.
The value grew with increasing negative value of the Hammett constant.
All porphyrins showed negative values both in neutral and acidic media.
The value of porphyrins increased three to five times in an acidic
medium compared to neutral. One species, 2[(>-0CH2C02C2Hs)PP], showed
values of -273.5 x 10 3(1 esu in acidic medium, about 5 times larger
than in the neutral medium. The H2[T(o-OCH2CO2C2H<0PP] material also
accorded a value 36 times larger than H2(TPP) in an acidic medium. The
NLO properties of H2[T(o-OCH2-C02C2H5)PP] were significantly higher than
the other materials because of the substituted electron donor groups at
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