  The search for sustainable alternatives to established materials is a
sensitive topic in materials science. Due to their unique structural and
physical characteristics, the composition of metal-organic frameworks (MOFs)
can be tuned by the exchange of the metal nodes and the functionalization of
the organic ligands giving rise to a large configurational space. Considering
the case of scandium terephthalate MOFs and adopting an automatized
computational framework based on density-functional theory, we explore the
impact of metal substitution with the earth-abundant isoelectronic elements Al
and Y, and of ligand functionalization of varying electronegativity. We find
that structural properties are strongly impacted by the metal ion substitution
and only moderately by ligand functionalization. In contrast, the energetic
stability, the charge density distribution, and the electronic properties -
including the size of the band gap - are primarily affected by the termination
of the linker molecules. Functional groups such as OH and NH$_2$ lead to
particularly stable structures thanks to the formation of hydrogen bonds and
affect the electronic structure of the MOFs by introducing mid-gap states.
