PHYS01200704032 Debes Ray - Homi Bhabha National Institute

d/d (cm -1 )
P(Q)
Chapter 3: Multi-Technique Approach for Characterization of Gold Nanoparticles
1
0.1
0.01
Q -2
Q -1
1E-3
1E-4
Sphere
Rod
Disc
1E-5
1E-6
0.001 0.01 0.1 0.3
Q (Å -1 )
Figure 3.17. P(Q)-dependence for different shapes of the particles.
2.00E+009
1.50E+009
1.00E+009
5.00E+008
0.00E+000
0.01 0.1 1
Q (Å -1 )
Figure 3.18. SAS data from a charged nanoparticle system in presence of varying ionic
strength. The increase in the value of cross-section in low-Q region corresponds to the
increasing ionic strength.
SAS data is obtained from the structure factor S(Q). The SAS data usually show a correlation
peak for interacting systems, whose position and width is decided by the number density and
interaction of the particles, respectively. Figure 3.18 shows typical SAS data from a charged
nanoparticle system in presence of varying salt (e.g. NaCl) concentration. It is seen that the
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