Surface-supported low-dimensional magnetic materials are of high fundamental interest and of significant
relevance for future applications, e.g., in nanoscale spintronics or quantum technology. Furthermore, they
could represent tunable model systems for, e.g., true single-layer frustrated two-dimensional (2D) quantum
spin lattices, which are very difficult to realize otherwise. This proposal includes the in-depth investigation of
chemically programmed and thereby tunable 2D and one-dimensional (1D) spin arrangements in a spectromicroscopy
approach combining X-ray magnetic circular dichroism (XMCD) with scanning tunneling microscopy
(STM). This uniquely allows us to study the interplay between competing magnetic interactions in single-layer
2D systems.