Dataset for publication: "Nonlinear nanomechanical mass spectrometry without mode-shape identification"

Nanomechanical mass spectrometry enables the detection and characterization of individual ionized and neutral particles through resonance-frequency shifts of mechanical resonators. Conventional approaches generally require prior knowledge of resonator mode shapes to determine the mass and location of deposited analytes. However, obtaining accurate mode-shape information becomes increasingly challenging in nanoscale devices, where limited linear dynamic range often leads to strong nonlinear effects that complicate resonance tracking and mass identification. This work introduces a nonlinear nanomechanical mass spectrometry framework that exploits the nonlinear dynamic response of resonators rather than suppressing it. The proposed approach enables analyte mass determination over a broad range, potentially from daltons to gigadaltons, for resonators of arbitrary geometry without requiring prior knowledge of their vibrational mode shapes. Mass estimation is based solely on shifts in bifurcation frequencies measured in two consecutive vibration modes. A theoretical model is developed to describe the underlying nonlinear mechanisms and establish the relationship between analyte mass and bifurcation-frequency shifts. The framework is validated experimentally using measurements from a nanomechanical resonator, while Monte Carlo simulations are employed to assess the accuracy and robustness of the mass estimates. The results demonstrate that nonlinear modal interactions provide sufficient information for accurate mass identification without mode-shape reconstruction, thereby overcoming a key limitation of existing nanomechanical spectrometry methods.