Environmental Molecular Sciences Laboratory

About: Environmental Molecular Sciences Laboratory is a facility organization based out in Richland, Washington, United States. It is known for research contribution in the topics: Mass spectrometry & Ion. The organization has 1471 authors who have published 3010 publications receiving 169961 citations.

Photoelectron Spectroscopy and Electronic Structure of ScOn- (n = 1−4) and YOn- (n = 1−5): Strong Electron Correlation Effects in ScO-and YO-

Abstract: A photoelectron spectroscopic study of ScOn- (n = 1−4) and YOn- (n = 1−5) was carried out at three photon energies: 532, 355, and 266 nm. Vibrationally resolved photoelectron spectra were obtained for ScO- and YO-. The electron affinities of both ScO and YO were measured to be identical (1.35 eV) within the experimental accuracy (±0.02 eV). Three low-lying excited states were observed for the monoxides, A‘2Δ, A2Π, and B2Σ+. The latter two excited states resulted from two-electron detachment, suggesting unusually strong electron correlation (configuration interaction) effects in the ground state of the anions. The excitation energies of the low-lying states were also found to be similar for the two monoxides except that YO has a smaller vibrational frequency and larger spin−orbit splitting. The A‘2Δ states of both ScO and YO show very strong photon energy-dependent detachment cross sections. Four similar photoelectron features were observed for the dioxides with those of YO2- having lower binding energies...

Revealing Cycling Rate-Dependent Structure Evolution in Ni-Rich Layered Cathode Materials

Abstract: High-rate cycling of a battery often leads to a compromised performance, such as reduced capacity, rapid voltage decay, and thermal runaway. Although the cycling rate-dependent performance is gener...

Automated gain control and internal calibration with external ion accumulation capillary liquid chromatography-electrospray ionization Fourier transform ion cyclotron resonance.

Abstract: When combined with capillary LC separations, electrospray ionization-Fourier transform ion cyclotron resonance mass spectrometry (ESI-FTICR MS) has demonstrated capabilities for advanced characterization of proteomes based upon analyses of proteolytic digests. Incorporation of external (to the ICR cell) multipole devices with FTICR for ion selection and ion accumulation has enhanced the dynamic range, sensitivity, and duty cycle of measurements. However, the highly variable ion production rate from an LC separation can result in “overfilling” of the external trap during the elution of major peaks and result in m/z discrimination and fragmentation of peptide ions. Excessive space charge trapped in the ICR cell also causes significant shifts in the detected ion cyclotron frequencies, reducing the achievable mass measurement accuracy (MMA) and making protein identification less effective. To eliminate m/z discrimination in the external ion trap, further increase duty cycle, and improve MMA, we have developed...

Lipid and Glycolipid Isomer Analyses Using Ultra-High Resolution Ion Mobility Spectrometry Separations.

Abstract: Understanding the biological roles and mechanisms of lipids and glycolipids is challenging due to the vast number of possible isomers that may exist. Mass spectrometry (MS) measurements are currently the dominant approach for studying and providing detailed information on lipid and glycolipid presence and changes. However, difficulties in distinguishing the many structural isomers, due to the distinct lipid acyl chain positions, double bond locations or specific glycan types, inhibit the delineation and assignment of their biological roles. Here we utilized ultra-high resolution ion mobility spectrometry (IMS) separations by applying traveling waves in a serpentine multi-pass Structures for Lossless Ion Manipulations (SLIM) platform to enhance the separation of selected lipid and glycolipid isomers. The multi-pass arrangement allowed the investigation of paths ranging from ~16 m (one pass) to ~60 m (four passes) for the distinction of lipids and glycolipids with extremely small structural differences. These ultra-high resolution SLIM IMS-MS analyses provide a foundation for exploring and better understanding isomer-specific biological activities and disease processes.