Procedure to Obtain Morphological Data from ID SAXS Profiles

APPENDIX A PROCEDURE TO OBTAIN MORPHOLOGICAL DATA FROM ID SAXS PROFILES 

If enough data is acquired at large q values, and 4 can be determined using nonlinear least-squares fitting and, therefore, the ideal intensity. However, the problem arises in the selection of q limits, since the choice of both the lower and upper limits significantly affects the validity of the Porod s law. In this case, the upper limit was set to ( upp = 2, and the lower limit q was varied until the minimum area of the interference function G iq) was obtained (Eq. 19.53). Once this criterion is achieved, the interface distribution function gi(r) (Eq. 19.54) is calculated from the Eourier transform of G iq). 

Tj corresponds to the tth interface distance, and to its corresponding standard deviation. Interface distances and their distributions were obtained by means of a nonlinear least-squares fitting of the /ideaiC ) 0 to Equation (19.A.2). A weight factor of l//ideai( ) 0 was used. The periodicity or long period L is the sum of + r2- The resulting parameters are shown in Tables 19.A.1 and 19.A.2. Finally, the ideal intensity, the Lorentz intensity, the interference function, and the interface distribution function were 

TABLE 19.A.1 Experimental Parameters Obtained in Reciprocal-Space Analysis 

TABLE 19.A.2 Experimental Parameters Obtained in Real-Space Analysis  

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