Protonated water clusters, H+(H2O)n (n = 5−8), from a supersonic expansion have been investigated by vibrational predissociation spectroscopy and ab initio calculations. The experimental spectra were obtained at an estimated cluster temperature of 170 ± 20 K. Recorded absorption bands the frequency range 2700−3900 cm-1 are attributed to free- hydrogen-bonded-OH stretches ion core surrounding solvent molecules. Ab calculations, performed B3LYP/6-31+G* level, indicate that geometries...

In a Fourier transform-ion cyclotron resonance mass spectrometer the gas phase reactivities of niobium clusters Nb+n (n=1–28) with molecular hydrogen, water, methane, ethane, n-propane, n-heptane, cyclohexane, acetylene, ethylene, allene, benzene, propene, toluene, xylene, and acetonitrile were investigated under single collision conditions as well oxidized cluster cations ethylene benzene. The reactions larger variety unsaturated hydrocarbons are believed to proceed via long lived...

The Schiff base compound 2,2′-{[(2-aminoethyl)imino]bis[2,1-ethanediyl-nitriloethylidyne]}bis-2-hydroxy-benzoic acid (H4L) as a proligand was prepared in situ. This has three potential coordination pockets which make it possible to accommodate from one metal ions allowing for the formation of mono-, di-, and trinuclear complexes. Reaction situ H4L with Dy(NO3)3·5H2O resulted mononuclear complex [Dy(H3L)2](NO3)·(EtOH)·8(H2O) (1), shows SMM behavior. In contrast, reaction Mn(ClO4)2·6H2O...

Gaining chemical control over the thermodynamics and kinetics of photoexcited states is paramount to an efficient sustainable utilization photoactive transition metal complexes in a plethora technologies. In contrast energies charge transfer described by spatially separated orbitals, spin-flip cannot straightforwardly be predicted as Pauli repulsion nephelauxetic effect play key roles. Guided multireference quantum calculations, we report novel highly luminescent emitter with chemically...

Photoactive complexes with earth-abundant metals have attracted increasing interest in the recent years fueled by promise of sustainable photochemistry. However, sophisticated ligands complicated syntheses are oftentimes required to enable photoactivity nonprecious metals. Here, we combine a cheap metal simple easily access photoactive complex. Specifically, synthesize molybdenum(0) carbonyl complex Mo(CO)3(tpe) featuring tripodal ligand 1,1,1-tris(pyrid-2-yl)ethane (tpe) two steps high...

A three-dimensional quantum mechanical study of vibrational state resolved differential cross sections for the direct inelastic and charge transfer channels H++H2 system has been carried out at Ecm =20 eV using infinite order sudden approximation (IOSA). Steric factors, opacity functions, angular distributions, integral are calculated. The in very good agreement with recent experimental results, whereas distributions agree only partially experiments. further comparison both theoretical...

The determination of spin and orbital magnetic moments from the free atom to bulk phase is an intriguing challenge for nanoscience, in particular, since most recording materials are based on nanostructures. We present temperature-dependent x-ray circular dichroism measurements Co clusters ($N=8--22$) which intrinsic noninteracting nanoparticles have been deduced. An exceptionally strong enhancement moment verified 4--6 times larger than value. Our reveal that orientation along external field...

Hydrated aluminum cluster cations Al+(H2O)n with n = 3−50 were stored in a collision-free environment, and their unimolecular fragmentation induced by the room temperature “black body” infrared background was studied. An interesting size-dependent intracluster reaction resulting oxidation of cation elimination molecular hydrogen observed. The results are discussed compared similar recent studies hydrated magnesium clusters.

The doubly differential cross sections for both the scattered protons and H atoms have been measured at ELAB=30 eV (ECM=20 eV) from θLAB=0° to 12° (θCM=0° 18°) reactions H++H2(v=0)→H++H2(vf) →H+H+2(vf) . energy resolution is sufficient resolve final vibrational states in channels. comparison of angular loss distributions two product channels provides first clear experimental evidence a two-step charge transfer mechanism: Vibrational excitation on lower H++H2 surface followed by outgoing...

The ruthenium-catalyzed hydroamidation of terminal alkynes has evolved to become a broadly applicable tool for the synthesis enamides and enimides. Depending on catalyst system employed, reaction leads chemo-, regio-, stereoselectively single diastereoisomer. Herein, we present comprehensive mechanistic study alkynes, which includes deuterium-labeling, in situ IR, NMR, ESI–MS experiments complemented by computational studies. results support involvement ruthenium–hydride ruthenium–vinylidene...

We present size dependent spin and orbital magnetic moments of cobalt (Con (+), 8 ≤ n 22), iron (Fen 7 17), nickel cluster (Nin 17) cations as obtained by X-ray circular dichroism (XMCD) spectroscopy isolated clusters in the gas phase. The range between corresponding atomic bulk values all three cases. compare our findings to previous XMCD data, Stern-Gerlach computational results. discuss application scaling laws evolution per atom clusters. find a law "per diameter," ∼n(-1/3), that...

We report IR active N2 stretching frequencies in isolated and size selected cobalt cluster nitrogen adsorbate complexes, [Con(N2)1](+) as recorded by virtue of InfraRed Photon Dissociation (IRPD) spectroscopy. The observed the complexes (n = 8-17) are significantly redshifted (2180 to 2290 cm(-1)) with respect inactive vibrations free (2359 cm(-1)). These bands assigned a μ1 head-on type coordination surface, revealing remarkable dependent features interpret.

The development of NIR emitters based on earth-abundant elements is an important goal in contemporary science. We present here Cr(0), Mo(0), and W(0) carbonyl complexes with a pyridyl-mesoionic carbene (MIC) ligand. A detailed photophysical investigation shows that all the exhibit dual emissions VIS region. emissive excited states are assigned to two distinct triplet by time-resolved emission step-scan FTIR spectroscopy at variable temperature, supported density functional theory. In...

Twofold cryo N₂ cleavage by Ta₄⁺ clusters occurs <italic>via</italic> a multistep across edge-above surface (AEAS) mechanism submerged barriers.

In spite of intense, recent research efforts, luminescent transition metal complexes with Earth-abundant metals are still very rare owing to the small ligand field splitting 3d and resulting non-emissive low-energy metal-centered states. Low-energy excited states decay efficiently non-radiatively, so that near-infrared emissive even more challenging. We report heteroleptic pseudo-octahedral d2-vanadium(iii) complex VCl3(ddpd) (ddpd = N,N'-dimethyl-N,N'-dipyridine-2-yl-pyridine-2,6-diamine)...

Cr(ppy)3, a structural analog of the green phosphorescent Ir(ppy)3, emits even in solution at room temperature from weakly distorted spin-flip state 910 nm (Hppy = 2-phenylpyridine). The low energy arises an enhanced covalence Cr-C bonds as compared to Cr-N bonds. Lower reduces thermally activated decay increasing emission intensity.

Size-selected hydroxide ion water tetramers and pentamers [OH-(H2O)4,5], produced by a supersonic expansion, have been investigated using vibrational predissociation spectroscopy in conjunction with ab initio calculations based on density functional theory (DFT). The observed spectra the frequency range 2650–3850 cm−1 show some broad absorption bands attributed to free hydrogen bonded OH stretches of OH-(H2O)4,5 at an estimated cluster temperature 170 K. DFT performed B3LYP/6-31 + G* level...

The existence of a transitional size regime where preferential stabilization alternates between "all-surface" (all atoms on the surface cluster) and "internally solvated" (one water molecule at center cluster, fully solvated) configurations with addition or removal single molecule, predicted earlier flexible, polarizable (many-body) Thole-type model interaction potential (TTM2-F), has been confirmed from electronic structure calculations for (H2O)n, n = 17-21. onset appearance first...

The gas phase infrared spectrum (3250–3810cm−1) of the singly hydrated ammonium ion, NH4+(H2O), has been recorded by action spectroscopy mass selected and isolated ions. four bands obtained are assigned to N–H stretching modes O–H modes. observed blueshifted with respect corresponding free NH4+ whereas a redshift is NH3 molecule. redshifted when compared H2O asymmetric give rise rotationally resolved perpendicular transitions. K-type equidistant rotational spacings 11.1(2)cm−1 (NH4+)...

Two AgI ions, deprotonated 1-methyl-thymine (1MT-H)− and 1,3-dideaza-adenine (DDA), self-assemble in methanolic solution to a cationic [(Ag)2(1MT-H)(DDA)]+ complex as identified by electrospray ionization mass spectrometry. Assignment of vibrational bands identification the silver coordination pattern arise from comparison one- two-color Infrared Multiple Photon Dissociation (IRMPD) spectra (1000–4000 cm−1) isolated trapped complexes calculated density functional theory. This approach...