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CS2 is Cyanogen Chloride-derived structured and crystallizes in the orthorhombic Cmce space group. The structure is zero-dimensional and consists of four CS2 clusters. C4+ is bonded in a linear geometry to two equivalent S2- atoms. Both C–S bond lengths are 1.56 Å. S2- is bonded in a single-bond geometry to one C4+ atom.
This is the AmeriFlux Management Project (AMP) created FLUXNET-1F version of the carbon flux data for the site US-CS2 Tri county school Pine Forest. This is the FLUXNET version of the carbon flux data for the site US-CS2 Tri county school Pine Forest produced by applying the standard ONEFlux (1F) software. Site Description - Tri county school Forest
Cs2(WO4)3 crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are two inequivalent Cs sites. In the first Cs site, Cs is bonded in a 7-coordinate geometry to eleven O atoms. There are a spread of Cs–O bond distances ranging from 3.06–3.79 Å. In the second Cs site, Cs is bonded in a 12-coordinate geometry to five O atoms. There are a spread of Cs–O bond distances ranging from 3.11–3.45 Å. There are three inequivalent W sites. In the first W site, W is bonded to six O atoms to form corner-sharing WO6 octahedra. The corner-sharing octahedra tilt angles range from 28–30°. There are a spread of W–O bond distances ranging from 1.78–2.07 Å. In the second W site, W is bonded to six O atoms to form corner-sharing WO6 octahedra. The corner-sharing octahedra tilt angles range from 30–32°. There are a spread of W–O bond distances ranging from 1.81–2.02 Å. In the third W site, W is bonded to six O atoms to form distorted corner-sharing WO6 octahedra. The corner-sharing octahedra tilt angles range from 28–32°. There are a spread of W–O bond distances ranging from 1.77–2.09 Å. There are twelve inequivalent O sites. In the first O site, O is bonded in a bent 150 degrees geometry to one Cs and two W atoms. In the second O site, O is bonded in a 1-coordinate geometry to two Cs and one W atom. In the third O site, O is bonded in a bent 150 degrees geometry to one Cs and two W atoms. In the fourth O site, O is bonded in a distorted single-bond geometry to two Cs and one W atom. In the fifth O site, O is bonded in a distorted single-bond geometry to two Cs and one W atom. In the sixth O site, O is bonded in a bent 150 degrees geometry to one Cs and two W atoms. In the seventh O site, O is bonded in a bent 150 degrees geometry to one Cs and two W atoms. In the eighth O site, O is bonded in a distorted single-bond geometry to one Cs and one W atom. In the ninth O site, O is bonded in a bent 150 degrees geometry to one Cs and two W atoms. In the tenth O site, O is bonded in a 1-coordinate geometry to two Cs and one W atom. In the eleventh O site, O is bonded in a 1-coordinate geometry to two Cs and one W atom. In the twelfth O site, O is bonded in a bent 150 degrees geometry to two W atoms.
Abstract Structural imaging of transient excited-state species is a key goal of molecular physics, promising to unveil rich information about the dynamics underpinning photochemical transformations. However, separating the electronic and nuclear contributions to the spectroscopic observables is challenging, and typically requires the application of high-level theory. Here, we employ site-selective ionisation via ultrashort soft X-ray pulses and time-resolved Coulomb explosion imaging to interrogate structural dynamics of the ultraviolet photochemistry of carbon disulfide. This prototypical system exhibits the complex motifs of polyatomic photochemistry, including strong non-adiabatic couplings, vibrational mode couplings, and intersystem crossing. Immediately following photoexcitation, we observe Coulomb explosion signatures of highly bent and stretched excited-state geometries involved in the photodissociation. Aided by a model to interpret such changes, we build a comprehensive picture of the photoinduced nuclear dynamics that follows initial bending and stretching motions, as the reaction proceeds towards photodissociation.
Tracking the multifarious ultrafast electronic and structural changes occurring in a molecule during a photochemical transformation is a challenging endeavor that benefits from recent experimental and computational progress in time-resolved techniques. Measurements of valence electronic states, which provide a global picture of the bonding structure of the molecule, and core electronic states, which provide insight into the local environment, traditionally require different approaches and are often studied separately. Here, we demonstrate that X-ray pulses from a seeded free-electron laser (FEL) enable the measurement of high-resolution, time-resolved X-ray photoelectron spectra (XPS) that capture weak satellite states resulting from shake-down processes in a valence-excited molecule. This approach effectively combines the advantages of both valence- and core-state investigations. We applied this method to investigate photoexcited CS2 molecules, where the role of internal conversion (IC) and intersystem crossing (ISC) in determining the predissociation dynamics is controversial. We present XPS spectra from photoexcited CS2, obtained at the FERMI FEL. High-resolution measurements, compared to the corresponding spectra obtained from accurate multireference quantum chemical calculations, reveal that shake-down satellite channels are highly sensitive to both valence electronic and geometric changes. Previous studies of the predissociation dynamics have led to uncertain assignments of the branching between singlet and triplet excited states. We derive a propensity rule that demonstrates the spin-selectivity of the shake-downs. This selectivity allows us to unequivocally assign contributions from the bright and dark singlet excited states, with populations tracked along the predissociation dynamic pathway.
The dissociation dynamics of dissociative electron attachment to carbon disulfide is studied using the velocity map imaging technique. Ion yields of the S− and CS− fragments are measured as a function of incident electron energy between 2 and 12 eV. Energy and angle-differential yields of the S− fragments are analyzed to investigate the dynamics of the CS2− anion around the 3.8-eV peak. The resonances involved in this fragmentation are identified and characterized in calculations using the well-known R-matrix method. Based on our measurements and the geometry dependence of the calculated resonances, we propose that a geometrical distortion of the transient negative-ion state of CS2 is necessary for S-CS bond dissociation to occur.
Solar energy conversion requires the working compositions to generate photoinduced charges with high potential and the ability to deliver charges to the catalytic sites and/or external electrode. These two properties are typically at odds with each other and call for new molecular materials with sufficient conjugation to improve charge conductivity but not as much conjugation as to overly compromise the optical band gap. In this work, we developed a semiconducting metal-organic framework (MOF) prepared explicitly through metal-carbodithioate"(-CS 2 ) n M" linkage chemistry, entailing augmented metal-linker electronic communication. The stronger ligand field and higher covalent character of metal-carbodithioate linkages-when combined with spirofluorene-derived organic struts and nickel-(II) ion-based nodes-provided a stable, semiconducting 3D-porous MOF, Spiro-CS 2 Ni. This MOF lacks long-range ordering and is defined by a flexible structure with non-aggregated building units, as suggested by reverse Monte Carlo simulations of the pair distribution function obtained from total scattering experiments. The solvent-removed "closed pore"material recorded a Brunauer-Emmett-Teller area of similar to 400m 2 /g, where the "open pore" form possesses90 wt % solvent-accessible porosity. Electrochemical measurements suggest that Spiro-CS 2 Ni possesses a band gap of 1.57 eV(sigma = 10 -7 S/cm at -1.3 V bias potential),which can be further improved by manipulating the d-electron configuration through an axial coordination (ligand/substrate), the latter of which indicates usefulness as an electrocatalyst and/or a photoelectrocatalyst(upon substrate binding). Transient-absorption spectroscopy reveals a long-lived photo-generated charge-transfer state (τ CR = 6.5 mu s) capable of chemical transformation under a biased voltage. Spiro-CS 2 Ni can endure a compelling range of pH(1-12 for weeks) and hours of electrochemical and photoelectrochemical conditions in the presence of water and organic acids. We believe this work provides crucial design principles for low-density, porous,light-energy-conversion materials.
Aspects of the invention are associated with the discovery of approaches for the conversion of sour natural gas streams, by conversion to liquid hydrocarbons. Particular processes and their associated apparatuses advantageously combine (i) dehydroaromatization (DHA) of methane in a gaseous feedstock, to produce aromatic hydrocarbons such as benzene, with (ii) the reaction of H2S and methane in this feedstock, to produce organic sulfur compounds such as carbon disulfide (CS2) and thiophene (C4H4S). A gaseous product having a reduced concentration of H2S is thereby generated. The aromatic hydrocarbons and organic sulfur compounds may be recovered in a liquid product. Both the gaseous and liquid products may be easily amenable to further upgrading. Other advantages of the disclosed processes and apparatuses reside in their simplicity, whereby the associated streams, including a potential gaseous recycle, generally avoid high partial pressures of H2S.