Multivariate statistical analysis of spectrum lines and images

摘要

Recent developments in instrumentation and computing power have greatly improved the potential for quantitative imaging and analysis. Multivariate statistical analysis (MSA) provides a method for analyzing the raw data set as a whole. The information that can be extracted by MSA from a series of spectra is illustrated by an application to a TEM spectrum-line acquired with a Gatan Imaging Filter (GIF) at the Co-L edge for a phase boundary between the periclase- (CoO) and spinel- (Co3O4) structured phases of cobalt oxide. A series of 64 spectra, each of 512 channels, has been analyzed with MSA. The following MSA information is given: (1) logarithmic plot of the information content of the MSA-identified principle components of the series of spectra; (2) the spectrum line of the Co-L edge acquired with the GIF; (3) the first component of the variation; (4) the amplitude of the first component in each spectrum of raw data; (5) a second component; and (6) its amplitudes.