The Fourier transform microwave spectrum of 4-methylacetophenone recorded from 8 GHz to 18 under jet-cooled conditions has revealed large tunneling splittings arising a low barrier internal rotation the ring methyl group and small high torsional acetyl group. are especially challenging model, while difficult analyze due resolution limit 120 kHz. combination two groups undergoing rotations caused each rotational transition split into five species, which were resolved fitted using modified...

Homosalate has been found to exhibit favourable photophysics for inclusion in sunscreens, using a combination of spectroscopic and computational approaches.

Borazine is isoelectronic with benzene and popularly referred to as inorganic benzene. The study of non-covalent interactions borazine comparison its organic counterpart promises show interesting similarities differences. motivation the present borazine-water interaction, for first time, stems from such possibilities. Hydrogen-bonded complexes water were studied using matrix isolation infrared spectroscopy quantum chemical calculations. Computations performed at M06-2X MP2 levels theory...

The 4

Abstract The reaction between guanine radical cation (G +· ) and carbonate anion (CO 3 −· producing the mutagenic product 8‐oxoguanine that has been observed experimentally was investigated using density functional second‐order Møller–Plesset perturbation (MP2) theories. structures of reactant, intermediate, complexes as well those transition states were fully optimized at B3LYP/6‐31G**, B3LYP/AUG‐cc‐pVDZ, BHandHLYP/AUG‐cc‐pVDZ levels theory in gas phase. Single point energy calculations...

The rotational spectrum of 2-hexanone was recorded over the 8-18 GHz region using a chirped pulse Fourier transform microwave spectrometer. Strong field coherence breaking (SFCB) utilized to selectively modulate intensities transitions belonging two lowest energy conformers 2-hexanone, aiding assignment. In addition, SFCB method applied for first time identify built off hindered methyl rotor states each conformer, 0a1 and 1e. Since these have levels with different nuclear spin symmetries,...

The flash pyrolysis of <italic>trans</italic> 3-pentenenitrile was studied by mass-correlated broadband microwave spectroscopy, where both molecular and radical species were observed within our jet-cooled beam, including 2,4-pentadienenitrile.

The single-conformation ultraviolet and infrared spectroscopy of three short-chain para-dialkylbenzenes (para-diethylbenzene, para-dipropylbenzene, para-dibutylbenzene) is reported for the jet-cooled, isolated molecules. present study builds off previous work on single-chain n-alkylbenzenes, where an anharmonic local mode Hamiltonian method was developed to account stretch-bend Fermi resonance in alkyl CH stretch region [D. P. Tabor et al., J. Chem. Phys. 144, 224310 (2016)]. jet-cooled...

Understanding conformational preferences of 3- and 4-pentenenitriles<italic>via</italic>broadband microwave spectroscopy.

The rotational constants and quartic centrifugal distortion coefficients of hexafluoro-o-xylene were precisely derived from the 8 GHz to 18 gas phase microwave spectrum. In addition, all singly substituted 13C isotopologues determined. Instead intuitively expected symmetry C2v, as in o-xylene, calculations with a variety methods (B3LYP, CAM-B3LYP, ωB97XD, MP2, coupled-cluster singles, doubles, perturbative triples) predict C2 structure which two CF3 groups rotate opposite directions by about...

We utilize rotationally resolved Chirped-Pulse Fourier Transform millimeter-wave spectroscopy to study photodissociation dynamics of 1,3,5-Triazine (symmetric-Triazine) form 3 HCN molecules. The state-specific vibrational population distribution (VPD) the photofragments contains mechanistic details reaction. This is performed using 266 nm radiation transverse a seeded supersonic jet. cooling inefficiency in jet preserves VPD photofragments, while rotational enhances signal low-J...

We report cluster-specific vibrational and electronic spectra of propylbenzene(pBz)-water clusters sizes pBz(H2O)n with n=2-4, building upon previous work on benzene(Bz)-water clusters. For the clusters, we recorded resonant 2-photon ionization (R2PI) spectra, as well ion-dip infrared (RIDIR) in OH CH stretch regions, infrared-ultraviolet hole-burning (IR-UV HB). Due to flexibility hydrocarbon monomer cluster, a large number calculated minima were obtained. However, experimentally,...

This talk focuses on the single-conformation spectroscopy of small-chain para-dialkylbenzenes.This work builds previous studies from our group long-chain n-alkylbenzenes that identified first folded structure in octylbenzene.The dialkylbenzenes are representative a class molecules common components coal and aviation fuel known to be present vehicle exhaust.We bring para-diethylbenzene, para-dipropylbenzene para-dibutylbenzene into gas phase cool supersonic expansion.The jet-cooled then...

Titan, a moon of Saturn, has an atmosphere that is similar to prebiotic earth, which nitrogen rich.Pentenenitriles are importance as they potential precursors hetro-aromatic compounds like pyridine.This talk will describe our broadband microwave studies trans 3-pentenenitrile (t-3PN) under jet-cooled conditions.Strong-field coherence breaking (SFCB) was used selectively modulate the intensities transitions in conformer-specific manner, aiding analysis.Two conformers t-3PN were identified and...

of entirely new classes experiments, ranging from chiral sensing by three-wave mixing to microwave detection multichannel reaction kinetics. Yet, this is only the beginning. Future generations experiments will make increasingly creative use frequency-agile pulse sequences for coherent manipulation and interrogation molecular dynamics.