Stress induced alignment of Se chains in supercooled Ge5Se95 liquid

•Uniaxial stress-induced alignment of selenium chains in the structure of Ge5Se95 liquid is observed using 77Se NMR.•Selenium chain alignment results in inefficient atomic packing in the liquid structure.•Such chain alignment is related to the non-Newtonian shear thinning behavior in chalcogenide liquids.

The structural modifications in Ge5Se95 supercooled liquid under the application of a uniaxial compressive load are investigated using one- and two-dimensional 77Se nuclear magnetic resonance spectroscopy. The spectroscopic results clearly demonstrate a stress-induced alignment of selenium chains in the structure of the liquid in planes perpendicular to the loading axis. The topological modifications due to this selenium chain alignment result in inefficient atomic packing in the liquid structure that is manifested in a decrease in the glass density and may have important implications in understanding the pronounced non-Newtonian shear thinning behavior observed in Se-rich chalcogenide glasses/liquids.