Knowledge of the full phonon spectrum is essential to accurately calculate the dynamic disorder (σ) and hole mobility (μ h ) in organic semiconductors (OSCs). However, most vibrational spectroscopy techniques under-measure the phonons, thus limiting the phonon validation. Here, we measure and model the full phonon spectrum using multiple spectroscopic techniques and predict μ h using σ from only the Γ-point and the full Brillouin zone (FBZ). We find that only inelastic neutron scattering (INS) provides validation of all phonon modes, and that σ in a set of small molecule semiconductors can be miscalculated by up to 28% when comparing Γ-point against FBZ calculations. A subsequent mode analysis shows that many modes contribute to σ and that no single mode dominates. Our results demonstrate the importance of a thoroughly validated phonon calculation, and a need to develop design rules considering the full spectrum of phonon modes.

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Anomia ephippium (Oyster) shell has an inorganic "pseudo nacre" microstructure that is colored (white, yellow, orange, and red) with varying concentrations of organic polyene pigments. Using Brillouin laser light scattering, we measured the elastic constants of A. ephippium and Abalone prismatic and nacre microstructures. We find a direct correlation between the polyene concentration and the measured elastic stiffnesses of A. ephippium shells, suggesting that polyene pigment enhances the shell's primary function of mechanical protection. Further, Young's, bulk, and shear moduli of A. ephippium shells are found to surpass that of ultrastrong Abalone nacre. By studying both microstructures, we demonstrate that pseudo nacre is stiffer than nacre. This work sheds light on the structure−property relation of pseudo nacre and organic constituents that may potentially be a paradigm shift for the future mimicry of super strong biomaterials.