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1. Variation in δ ¹⁵ N and δ ¹³ C values of forages for Arctic caribou: effects of location, phenology and simulated digestion: Variation in δ ¹⁵ N and δ ¹³ C values of forages for Arctic caribou

   https://doi.org/10.1002/rcm.7849  

   Vansomeren, Lindsay L.; Barboza, Perry S.; Gustine, David D.; Syndonia Bret-Harte, M. (May 2017, Rapid Communications in Mass Spectrometry)
2. First detection and analysis of an electronic spectrum of vanadium hydride: The D ⁵ Π –X ⁵ Δ (0,0) band

   https://doi.org/10.1063/5.0105844  

   Varberg, Thomas D. (August 2022, The Journal of Chemical Physics)

   The D 5 Π–X 5 Δ (0,0) band of vanadium hydride at 654 nm has been recorded by laser excitation spectroscopy and represents the first analyzed spectrum of VH in the gas phase. The molecules were generated using a hollow cathode discharge source, with laser-induced fluorescence detected via the D 5 Π–A 5 Π (0,0) transition. All five main (ΔΩ = ΔΛ) subbands were observed as well as several satellite ones, which together create a rather complex and overlapped spectrum covering the region 15 180–15 500 cm −1 . The D 5 Π state displays the effects of three strong local perturbations, which are likely caused by interactions with high vibrational levels of the B 5 Σ − and c 3 Σ − states, identified in a previous multiconfigurational self-consistent field study by Koseki et al. [J. Phys. Chem. A 108, 4707 (2004)]. Molecular constants describing the X 5 Δ, A 5 Π, and D 5 Π states were determined in three separate least-squares fits using effective Hamiltonians written in a Hund’s case (a) basis. The fine structure of the ground state is found to be consistent with its assignment as a σπ 2 δ, 5 Δ electronic state. The fitted values of its first-order spin–orbit and rotational constants in the ground state are [Formula: see text] and B = 5.7579(13) cm −1 , the latter of which yields a bond length of [Formula: see text] Å. This experimental value is in good agreement with previous computational studies of the molecule and fits well within the overall trend of decreasing bond length across the series of 3d transition metal monohydrides. 

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3. B ₃₁ ⁻ and B ₃₂ ⁻ : chiral quasi-planar boron clusters

   https://doi.org/10.1039/C9NR01524H  

   Chen, Qiang; Chen, Teng-Teng; Li, Hai-Ru; Zhao, Xiao-Yun; Chen, Wei-Jia; Zhai, Hua-Jin; Li, Si-Dian; Wang, Lai-Sheng (May 2019, Nanoscale)

   Chirality plays an important role in nature. Nanoclusters can also exhibit chiral properties. We report herein a joint experimental and theoretical investigation on the geometric and electronic structures of B 31 − and B 32 − clusters, using photoelectron spectroscopy in combination with first-principles calculations. Two degenerate quasi-planar chiral C 1 enantiomers ( I and II , 1 A) with a central hexagonal vacancy are identified as the global minima of B 31 − . For B 32 − , two degenerate boat-like quasi-planar chiral C 2 structures ( VI and VII , 2 A) with a central hexagonal vacancy are also found as the global minima, with a low-lying chair-like C i B 32 − ( VIII , 2 A u ) also present in the experiment as a minor isomer. The chiral conversions in quasi-planar B 31 − and B 32 − clusters are investigated and relatively low barriers are found due to the high flexibility of these monolayer clusters, which feature multiple delocalized σ and π bonds over buckled molecular surfaces. 

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4. Planar B ₄₁ ⁻ and B ₄₂ ⁻ clusters with double-hexagonal vacancies

   https://doi.org/10.1039/C9NR09522E  

   Bai, Hui; Chen, Teng-Teng; Chen, Qiang; Zhao, Xiao-Yun; Zhang, Yang-Yang; Chen, Wei-Jia; Li, Wan-Lu; Cheung, Ling Fung; Bai, Bing; Cavanagh, Joseph; et al (December 2019, Nanoscale)

   Since the discovery of the B 40 borospherene, research interests have been directed to the structural evolution of even larger boron clusters. An interesting question concerns if the borospherene cages persist in larger boron clusters like the fullerenes. Here we report a photoelectron spectroscopy (PES) and computational study on the structures and bonding of B 41 − and B 42 − , the largest boron clusters characterized experimentally thus far. The PE spectra of both clusters display broad and complicated features, suggesting the existence of multiple low-lying isomers. Global minimum searches for B 41 − reveal three low-lying isomers ( I–III ), which are all related to the planar B 40 − structure. Isomer II ( C s , 1 A′) possessing a double hexagonal vacancy is found to agree well with the experiment, while isomers I ( C s , 3 A′′) and III ( C s , 1 A′) both with a single hexagonal vacancy are also present as minor isomers in the experiment. The potential landscape of B 42 − is found to be much more complicated with numerous low-lying isomers ( VII–XII ). The quasi-planar structure VIII ( C 1 , 2 A) containing a double hexagonal vacancy is found to make major contributions to the observed PE spectrum of B 42 − , while the other low-lying isomers may also be present to give rise to a complicated spectral pattern. Chemical bonding analyses show isomer II of B 41 − ( C s , 1 A′) and isomer VIII of B 42 − ( C 1 , 2 A) are π aromatic, analogous to that in the polycyclic aromatic hydrocarbon C 27 H 13 + ( C 2v , 1 A 1 ). Borospherene cage isomers are also found for both B 41 − and B 42 − in the global minimum searches, but they are much higher energy isomers. 

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5. Benchmark calculations of ro-vibrational spectrum of HeH ⁻ and its isotopologues

   https://doi.org/10.1088/1361-6455/abb126  

   Palikot, Ewa; Stanke, Monika; Adamowicz, Ludwik (November 2020, Journal of Physics B: Atomic, Molecular and Optical Physics)

   null (Ed.)