We propose a new chemical detection technique in which an analyte's vibrational frequencies are interrogated directly using an array of nanomechanical resonators. This "nanomechanical resonance spectroscopy" (NRS) could permit label-free chemical detection, combining the high sensitivity of nanomechanical approaches with the high selectivity of traditional spectroscopy. A computational proof of...

Ultrafast infrared spectroscopy can reveal the dynamics of vibrational excitations in matter. In its conventional far-field implementation, however, it provides only limited insight into nanoscale sample volumes due to insufficient spatial resolution and sensitivity. Here, we combine scattering-scanning near-field optical microscopy (s-SNOM) with femtosecond infrared vibrational spectroscopy to...

Lactate dehydrogenase (LDH) catalyzes the interconversion of pyruvate and lactate. Recent isotope-edited IR spectroscopy suggests that conformational heterogeneity exists within the Michaelis complex of LDH, and this heterogeneity affects the propensity toward the on-enzyme chemical step for each Michaelis substate. By combining molecular dynamics simulations with Markov and hidden Markov model...

High-resolution gas-phase infrared spectroscopy of buckminsterfullerene (C 60 ) was attempted near 8.5 μmusing cavity ring-down spectroscopy. Solid C 60 was heated in a high-temperature (∼950K) oven and cooled using an argon supersonic expansion generated from a 12.7mm × 150 μm slit.The expected S/N ratio is ∼140 for vibrationally cold C 60 , but no absorption signal has been observed, presumab...

In this chapter we review recent advances in theoretical methods to understand and rationalize anharmonic vibrational spectroscopy (IR-MPD and IR-PD) and collision induced dissociations (CID) in the gas phase. We focused our attention on the application of molecular dynamics-based methods. DFT-based molecular dynamics was shown to be able to reproduce InfraRed Multi-Photon Dissociation (IR-MPD)...

Vibrational spectroscopy has been widely applied in different fields due to its label-free chemical-sensing capability. Coherent anti-Stokes Raman scattering (CARS) provides stronger signal and faster acquisition than spontaneous Raman scattering, making it especially suitable for molecular imaging. Coherently-controlled single-beam CARS simplifies the conventional multi-beam setup, but the vib...

Polymorph detection, identification, and quantitation in crystalline materials are of great importance to the pharmaceutical industry. Vibrational spectroscopic techniques used for this purpose include Fourier transform mid-infrared (FT-MIR) spectroscopy, Fourier transform near-infrared (FT-NIR) spectroscopy, Raman spectroscopy, and terahertz (THz) and far-infrared (FIR) spectroscopy. Typically...

Photodetachment spectroscopy of OH(-) and H(3)O(2)(-) anions has been performed in a cryogenic 22-pole radiofrequency multipole trap. Measurements of the detachment cross section as a function of laser frequency near threshold have been analysed. Using this bound-free spectroscopy approach we could demonstrate rotational and vibrational cooling of the trapped anions by the buffer gas in the mul...

CONTENTS Introduction Ultraviolet and Visible Spectroscopy Nature of Electronic Transitions Principles of Absorption Spectroscopy Spectral Measurements Solvent Effects Applications of Electron Spectroscopy Commercial Applications of UV and Visible Spectroscopy Infrared Absorption Spectroscopy Hooke’s law and Absorption of Radiations Modes of Molecular Vibrations Other Factors influencing Vibrat...