ABSTRACT
TABLE 2 Parameters of the Dependence of vem on vcx for a Number of Polymer and Related Systems.
System Vpp1<*a' Range0 ir*d
(cm"1) Ae
(cm-1) l^ocd Ref.
PPV film 120/650 = 0.18 1 -2.2 to -2.1 -2 91
PPPV in MTHF 190/690 = 0.28 0.96 -2.7 to -1.3 _ _ -1.3 40
PPPV in MTHF 390/625 = 0.62 0.78 -1.6 to +2.1 -2200 270 (0-0) >0 89
PPPV in PC (1%)
stretched 0.5 <0 96 PPPV in PC
(1%) unstretch. 0.6 <0 96 PDA
in MTHF 155/550 = 0.28 0.98 -1.3 to -0.2 _ _ 99 PDT
in MTHF 240/875 = 0.27 1 -2.1 to -1.9 _ _ -1.8 97 PPP film 460/600
430/600 = 0.77 0.75 (0-0) = 0.72 0.8 (0-1)
1 (0-1)
-5.2 to -3.7
-7.9 to -5.2
-3300 365 (0-0) -2.7 95
IPNf in MTHF 40/120 = 0.33 0.97 -0.5 to +1.1 _ _ >0 99
Bromonaphthalene film 105/160 = 0.65 0.65 (0-0) -2.2 to +1.1 -330 70 (0-0) +2 34
tions in this spectral region. The dependence of crpp/a a on k, taken from Table 2, is shown in Fig. 15. The line presents relation (14) connecting these parameters in the model of “two Gaussians.” One can see that it qualitatively describes the ex perimental data. Therefore, in the region not very far from the IDF maximum, this model seems reasonable. We obtained also the values of Stokes losses A from Eq. (15), using the position of the intersection point v* for the 0 -0 transition and presented them in Table 2. Note also that as in the PPP film, the crossover from Jc < 1 to k = 1 behavior is also observed in PPPV dispersed in polycarbonate [96].
