In materials research, structural characterization often
requires
multiple complementary techniques to obtain a holistic morphological
view of a synthesized material. Depending on the availability and
accessibility of the different characterization techniques (e.g.,
scattering, microscopy, spectroscopy), each research facility or academic
research lab may have access to high-throughput capability in one
technique but face limitations (sample preparation, resolution, access
time) with other technique(s). Furthermore, one type of structural
characterization data may be easier to interpret than another (e.g.,
microscopy images are easier to interpret than small-angle scattering
profiles). Thus, it is useful to have machine learning models that
can be trained on paired structural characterization data from multiple
techniques (easy and difficult to interpret, fast and slow in data
collection or sample preparation) so that the model can generate one
set of characterization data from the other. In this paper we demonstrate
one such machine learning workflow, Pair-Variational Autoencoders
(PairVAE), that works with data from small-angle X-ray scattering
(SAXS) that present information about bulk morphology and images from
scanning electron microscopy (SEM) that present two-dimensional local
structural information on the sample. Using paired SAXS and SEM data
of newly observed block copolymer assembled morphologies [open access
data from DoerkG. S.
Doerk, G. S.
eadd3687Sci. Adv.20239], we train our PairVAE. After
successful training, we demonstrate that the PairVAE can generate
SEM images of the block copolymer morphology when it takes as input
that sample’s corresponding SAXS 2D pattern and vice versa.
This method can be extended to other soft material morphologies as
well and serves as a valuable tool for easy interpretation of 2D SAXS
patterns as well as an engine for generating ensembles of similar
microscopy images to create a database for other downstream calculations
of structure–property relationships.