The formation of water structures can provide significant benefits in organic reactions, stabilizing charge and lowering activation energies. Hydrolysis reactions will frequently rely on networks to accomplish these goals. Here, we used computational chemistry experimental kinetics investigate a model thioester molecule S-ethyl trifluorothioacetate, extended work previously characterized ester p-nitrophenyl trifluoroacetate. We found that the rate-determining steps are heavily influenced by...

The exothermicity of the chemi-ionization reaction Sm + O → SmO+ e− has been re-evaluated through combination several experimental methods. thermal reactivity (300–650 K) Sm+ and with a range species measured using selected ion flow tube-mass spectrometer apparatus is reported provides limits for bond strength SmO+, 5.661 eV ≤ D0(Sm+-O) 6.500 eV. A more precise value to be 5.725 ± 0.07 eV, bracketed by observed guided beam tandem mass (GIBMS). Combined established ionization energy (IE),...

The temperature dependences of the rate constants and product branching ratios for reactions FeO(+) with CH4 CD4 have been measured from 123 to 700 K. 300 K are 9.5 × 10(-11) 5.1 cm(3) s(-1) reactions, respectively. At low temperatures, Fe(+) + CH3OH/CD3OD channel dominates, while at higher FeOH(+)/FeOD(+) CH3/CD3 becomes majority channel. data were found connect well previous experiments translational energies. kinetics simulated using a statistical adiabatic model (vibrations during...

Direct dynamics simulations and selected ion flow tube (SIFT) experiments were performed to study the kinetics of OH(-) + CH3I reaction versus temperature. This work complements previous direct simulation molecular beam imaging this collision energy (Xie et al. J. Phys. Chem. A 2013, 117, 7162). The are in quite good agreement. Both identify SN2, → CH3OH I(-), proton transfer, CH2I(-) H2O, reactions as having nearly equal importance. In experiments, SN2 pathway constitutes 0.64 ± 0.05, 0.56...

The reactions of FeO+ with H2, D2, and HD were studied in detail from 170 to 670 K by employing a variable temperature selected ion flow tube apparatus. High level electronic structure calculations performed compared previous theoretical treatments. Statistical modeling the isotope dependent rate constants was found reproduce all data, suggesting reaction could be well explained efficient crossing sextet quartet surface, rigid near thermoneutral barrier accounting for both inefficiency...

The reactions of FeO⁺ with H₂ and Fe⁺ N₂O were studied respect to the production reactivity electronically excited ⁴Fe⁺ cations.

An experimental and theoretical study of bismuth-doped aluminum clusters in the gas phase has revealed two particularly stable clusters, namely, Al3Bi Al5Bi. We show that their electronic structure can be understood terms aromatic "Jellium" models, respectively. Negative ion photodetachment spectra provide a fingerprint states AlnBi− (n = 1−5) anions, while investigations reveal nature orbitals involved. Together, findings all-metal cluster with 14 valence electrons is cyclic, planar...

The ion–molecule reactions Fe+ + N2O → FeO+ N2 and CO CO2, which catalyze the reaction CO2 N2, have been studied over temperature range 120–700 K using a variable selected ion flow tube apparatus. Values of rate constants for former two were experimentally derived as k2 (10−11 cm3 s−1) = 2.0(±0.3) (T/300)−1.5(±0.2) 6.3(±0.9) exp(−515(±77)/T) k3 (10−10 3.1(±0.1) (T/300)−0.9(±0.1). Characterizing energy parameters by density functional theory at B3LYP/TZVP level, are modeled, accounting...

The rates of the reactions Fe⁺ + N₂O → FeO⁺ N₂ and CO CO₂ are modeled by statistical rate theory accounting for energy- angular momentum-specific constants formation primary secondary cationic adducts their backward forward reactions.

Metal clusters featuring closed supershells or aromatic character usually exhibit remarkably enhanced stability in their cluster series. However, not all stable are subject to these fundamental constraints. Here, by employing photoelectron imaging spectroscopy and ab initio calculations, we present experimental theoretical evidence on the existence of unexpectedly open-shell clusters, which more than closed-shell counterparts. The stabilization Al-Mg is proposed originate from S-P molecular...

Photoelectron imaging experiments and detailed calculations are conducted on Aln− clusters (n = 3–6) a calibration method is developed for connecting experimental observations of photoelectron angular distributions to theoretical predictions. It shown that this can be used quantify the degree which molecular orbitals built from s- or p-like atomic orbitals. The highest occupied these small aluminum found contain varying degrees s–p mixing, with Al3− containing "most hybridized" orbital Al4−...

A novel technique using a flowing afterglow-Langmuir probe apparatus for measurement of temperature dependences rate constants dissociative recombination (DR) is presented. Low (~10(11) cm(-3)) concentrations neutral precursor are added to noble gas∕electron afterglow plasma thermalized at 300-500 K. Charge exchange yields one or many cation species, each which may undergo DR. Relative ion monitored fixed reaction time while the initial density varied between 10(9) and 10(10) cm(-3)....

The electronic structure of Al(n)X (n = 1-6; X As, Sb) clusters has been investigated using a synergistic approach combining negative ion photoelectron spectroscopy and first principles calculations. It is shown that Al(3)X Al(5)X exhibit enhanced energetic stability, as evidenced from calculated removal embedding energies well chemical stability manifested through large gap between the highest occupied molecular orbital (HOMO) lowest unoccupied (LUMO). However, stabilities these species are...

We report for the first time temperature dependences (from 300 to 600 K) of reactions Fe+ and FeO+ with NO NO2. Both ions react quickly NO2, their rate constants have weak negative dependences. The former is consistent calculated energy profile along + NO2 reaction coordinate. Ground state reacts produce only FeO+, while NO+ exclusively. Certain source conditions excited Fe+, as evidenced by production primary NO+, which endothermic ground 0.35 eV. room are in agreement previous values. For...

Rate constants for the reactions of O2(-) and O(-) with N O atoms have been measured first time as a function temperature from 173 to 500 K 400 reactions. Room rate reacting are 3.1 × 10(-10) 1.7 cm(3) s(-1), respectively, corresponding 1.5 in good agreement previous values. Temperature dependences about T(-1.7) both T(-0.6) T(-1.3) O, respectively. Branching reaction is found predominantly form (>85%) contrast measurements, which reported NO2 + e(-) main channel. Calculations point present...

The temperature dependent kinetics of Ni+ + O3 and NiO+ CH4/CD4 are measured from 300 to 600 K using a selected-ion flow tube apparatus. Together, these reactions comprise catalytic cycle converting CH4 CH3OH. reaction proceeds at the collisional limit, faster than previously reported K. product reacts further with O3, also yielding both higher oxides (up NiO5+ is observed) as well undergoing an apparent reduction back Ni+. This channel due oxidation NiO2+* sufficient energy dissociate....

We present rate constants and product branching ratios for the reactions of FeOx+ (x = 0-4) with ozone at 500 K. Fe+ is observed to react collision produce FeO+ + O2. The in turn reacts yield both FeO2+ channels. Ions up FeO4+ display similar reactivity patterns. Three-body clustering O2 prevent us from measuring accurate 300 K although data do suggest that efficiency also high. Therefore, it probable little no temperature dependence exists over this range. Implications our measurements...

Synergistic studies of bismuth doped tin clusters combining photoelectron spectra with first principles theoretical investigations establish that highly charged Zintl ions, observed in the condensed phase, can be stabilized as isolated gas phase through atomic substitution preserves overall electron count but reduces net charge and thereby avoids instability because coulomb repulsion. Mass spectrometry reveal Sn8Bi−, Sn7Bi2−, Sn6Bi3− exhibit higher abundances than neighboring species,...

Three-dimensional aromaticity is shown to play a role in the stability of deltahedral Zintl clusters and here we examine connection between stability. In order gain further insight, have studied analogs comprised bismuth doped tin with photoelectron spectroscopy theoretical methods. To assign aromaticity, ring currents induced around cage by using nucleus independent chemical shift. current study, BiSn4− stable cluster fits aromatic criteria, while BiSn5− found fit antiaromatic criteria has...

We have measured reaction rate constants for CO+ and CO2+ reacting with N O atoms using a selected ion flow tube apparatus equipped microwave discharge atom source. Experimental work was supplemented by molecular structure calculations. Calculated pathways show the sensitivity of kinetic barriers to theoretical methods imply that high-level ab initio are required accurate energetics. report room-temperature 1.0 ± 0.4 × 10-11 cm3 s-1 4.0 1.6 reactions atoms, respectively, 8.0 3.0 10-12 2.0...

The electronic structure and stability of neutral negatively charged BixIny (x = 1−4, y 1−6) clusters are investigated through anionic photoelectron spectroscopy employing magnetic bottle velocity map imaging experiments. Experimental theoretical adiabatic vertical detachment energies the species containing up to 4 Bi In atoms deduced from first principles calculations. Among series, many found exhibit special in mass spectra, a large gap between highest occupied lowest unoccupied molecular...

The stability and electronic properties of anionic neutral PbxIny clusters containing up to 5 Pb 7 In atoms have been investigated using negative ion photodetachment spectroscopy along with first-principles structure studies within a gradient corrected density functional approach. Through the detachment energies, gaps in spectrum, variations binding energy, nature states, two families stable species are identified. PbIn3−, Pb2In2, Pb3In2 exhibit enhanced compared their neighbors is linked...