Mount for spectroscopic analysis of samples under sustained tensile stress.

This article focuses on the development and validation of a novel solid open-mount apparatus designed to enable in situ spectroscopic measurements of materials under sustained tensile stress, specifically using vibrational sum-frequency generation (VSFG) spectroscopy. The mount maintains the position of the sample plane during deformation, ensuring consistent overlap of laser beams critical for accurate spectroscopic data collection. Experiments with hydroxyl-terminated polybutadiene (HTPB), an elastomer, and high-density polyethylene (HDPE), a plastic, demonstrated the mount's ability to capture dynamic molecular and structural changes during tensile loading that are not accessible through pre- and post-deformation measurements alone. The design is adaptable to other spectroscopic techniques requiring precise sample positioning, such as Raman and reflection spectroscopy, and offers a practical tool for advancing the understanding of material behavior under mechanical stress.