Abstract: Recent results of structural and analytical characterization of AgX (X $EQ Br, I) microcrystals of photographic emulsions by a number of cryo-analytical electron microscopy (AEM) and image analysis techniques are presented. Monte Carlo simulations of electron beam-AgX interactions have been made for a better understanding of relationships between various signals which can be analyzed in the corresponding AEM modes. Combined cryo-ESI/EDX multielement mapping was performed on AgX grain thin sections and on tabular AgX microcrystals. The contrast imaging under filtering with selected energy windows has been applied to image the morphology, crystal and defect structures of composite tabular AgX microcrystals. Extra reflections at commensurate positions in between the main Bragg reflections and weak diffuse intensity honeycomb contours caused by twins and/or $LFBC@111$RTBC stacking faults in the shell region parallel to $LFBC@112$RTBC grain edges and polyhedral clusters of Ag$+$PLU$/ interstitials, respectively, were found in selected-area electron spectroscopic diffraction patterns. Low-loss collective excitations due to plasmons and excitons possibly superimposed with interband transitions and many- electron effects were revealed by cryo-EFTEM/EELS. The real and imaginary parts of dielectric permittivity were determined by means of a Kramers-Kronig analysis. Elemental inner shell edges of Ag and halides above 50 eV energy loss have been detected by EELS in accordance with cryo-STEM/EDX- analyses. The local crystal thickness was determined by a modified EELS log-ratio technique in agreement with measurements on grain replicas.!12
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