Single Particle Light Scattering Size Analysis: Quantification and elimination of the effect of particle shape and structure

Abstract

Abstract When measuring scattered light from single particles (as realized in various methods of scattered light‐particle size counting analysis) nonspherical particles and particles with inner structure produce different signal heights (scattered light intensities) when differently oriented in the measuring volume. To study the influence of the particle shape and structure, the representative spectrum of all signal heights reflecting all of the possible orientations of the particle in the measuring volume was recorded from individual particles of a definite material in each case. Additionally from every particle an equivalent diameter was determined. The measurements lead to a very precise calibration curve and to a transformation matrix, that describes the influence of shape and structure on scattered light‐counting analyses in case of the specific material. It is then possible to simulate measurements to determine the loss in resolution caused by the influence of shape and structure and to eliminate this effect from conventional scattered light analyses. The paper presents the concept together with results of simulation and elimination calculations for the material limestone and quartz. The corrected size distributions are compared with results by other methods. On the basis of this comparison it is discussed how successful the method is to recover a higher resolution.