Mechanoscientific
research fields encompassing chemistry,
physics,
and biology have advanced significantly over the last two decades.
Notably, the study of photon-emitting phenomena in molecular solids
responsive to mechanical stimulation is known as mechanoresponsive
luminescence (MRL) and mechanoluminescence (ML). These phenomena exhibit
significant potential for applications such as sensor technology and
anti-counterfeiting measures. The versatility observed in molecular
designs, enabling control over responsive thresholds and wavelengths,
coupled with diverse mechanisms for inducing deformation, such as
heat, light, and sound, significantly broadens the domain of mechanically
sensitive molecular materials. However, the understanding of the nanomechanical
aspects about these molecular solids remains elusive. A comprehensive
examination of the interplay among molecular structures, deformation
characteristics, and luminescence responses is essential for further
exploration. Such insights are crucial for addressing the intrinsic
limitation of “one-time use” associated with deformation-induced
properties, necessitating a focus on solid-state healing processes
as well. Recent investigations into inorganic-based ML systems applied
to free-standing light sources and mechanical metamaterial design
foreshadow the future trajectory of molecular-based systems. These
advancements aim to facilitate the secondary use of generated photons
and the efficient capture/transfer of mechanical cues, enhancing optical
output. Molecular luminescence stands poised to make substantial contributions
to the ongoing rapid progress in mechanoscience due to an expanding
synthetic repertoire, heightened biocompatibility, and precise “structural
control” at molecular and macroscopic scales.