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We study theoretically strong field effects in rotational femtosecond degenerate four-wave-mixing (DFWM). First, we developed a perturbative approach and calculated the leading correction to the standard (weak field) formula for femtosecond DFWM signal. Second, we constructed a nonperturbative approach for computing femtosecond DFWM signals excited by (short) pulses of arbitrary intensity. Third, we worked out the theory to describe femtosecond DFWM with an extra aligning pulse. We show that the strong-pulse-induced nonadiabatic alignment does explain many experimentally detected features that develop in femtosecond DFWM signals with increasing laser intensity beyond the standard weak field regime. However, we also show that this nonadiabatic alignment cannot solely be responsible for the onset of the heterodyne detection and pronounced constant background in DFWM signals excited by high intensity laser pulses. [ABSTRACT FROM AUTHOR]

We report on gas phase UV action spectroscopy and photodynamics of [Ag 3 (1MT-H/1MU-H) 2 ] + comprised of a linear silver string and two deprotonated 1-methyl-thymine/uracil (1MT/1MU) ligands. We applied pump–probe femtosecond laser photofragmentation in an electrospray ion trap mass spectrometer and high-level ab initio calculations at the level of approximate coupled-cluster singles-doubles theory. The experimental UV band at 283/275 nm is assigned to a red shifted 1 ππ ∗ nucleobase located transition. Relaxation of the 1 ππ ∗ state occurs with time constants of 0.2/1.1 ps and 0.2/4.2 ps for the 1MT and 1MU complexes, respectively, on a similar ultrafast time scale as non-metalated uracil derivatives. [ABSTRACT FROM AUTHOR]

In this paper, we report the use of femtosecond time-resolved degenerate four-wave mixing rotationally resolved spectroscopy to obtain very accurate structural information on the symmetric top cyclohexane. Apart from highlighting the versatility of this method in determining accurate structures of large and complex molecules without dipole moment, the present study also details the comparison of the experimentally determined rotational constant B[subo] with that obtained from high-level ab initio calculations. The theoretical calculations, which were carried out at both the second-order Møller-Plesset (MP2) and coupled-cluster with single, double, and perturbative triple substitutions [CCSD(T)] levels of theory, also take into account vibrational averaging effects. A detailed investigation of the vibrational averaging effects reveals that the corrections emerge from only the six highly symmetric A19 modes, a justification of which is provided by an analysis of these modes. [ABSTRACT FROM AUTHOR]

Correlated ab initio calculations are compared with experimental data from time-resolved rotational spectroscopy for the rotational constants of the phenol dimer. This system poses a challenge to theory since both hydrogen bonding and dispersion interaction are determining its unique geometry. Excellent agreement is obtained at the RI-MP2/TZVPP level of theory, demonstrating that higher order polarization functions are necessary for an accurate structural description. The computed intermolecular frequencies, stabilization energy and enthalpy are also reported. [Copyright &y& Elsevier]

The application of high-resolution pump–probe rotational coherence spectroscopy (RCS) provides precise rotational constants of large molecules and clusters for both the ground and the electronically excited states. A variety of experimental implementations are now available and described in the text. We give examples for these implementations and emphasize recent developments in this field. In particular, state-selective, mass-selective and four-wave mixing schemes are discussed for the molecules p-cyclohexylaniline (pCHA), cyclohexylbenzene (CHB), benzene, p-difluorobenzene (pDFB) and the clusters phenol dimer and pDFB–Ar. New results for CHB, benzene and pDFB by pump–probe photoionization and degenerate four-wave mixing are reported. The combination of different experimental methods and the comparison with theory based on ab initio calculations leads to a detailed description of the corresponding molecular structure. Finally, an outlook for future directions of RCS is presented. [Copyright &y& Elsevier]

A high-resolution two-color spectrometer for rotational coherence spectroscopy (RCS) in the picosecond time domain has been developed and applied to several molecular systems. This time-resolved method enables the structural characterization of large molecules and clusters in the gas phase by determination of their rotational constants with high precision. Our spectrometer is based on a well stabilized solid-state chirped pulse amplified laser setup with an adjustable pulse duration in the picosecond range. Two optical parametric generators provide tunable radiation in the UV spectral range, with a pulse duration of 2 ps. An interferometric setup is employed in order to perform pump-probe experiments with up to 8 ns delay between pump and probe pulse. Two different pulse to pulse switching modes and the online monitoring of laser parameters have been integrated to enable the measurement of RCS traces with high resolution and good signal/noise ratio. These modes also permit the identification of weak features that would otherwise not have been observed. The molecular samples are prepared in a supersonic expansion and either the laser induced fluorescence or the photoion current are detected as a function of the time delay between pump and probe pulse. The performance of the spectrometer is demonstrated by recording a high-resolution RCS spectrum of para-difluorobenzene·argon and benzene. From their analysis the rotational constants of the ground state and electronically excited state of both species were obtained with an estimated uncertainty on the order of 10[sup -4] and 10[sup -5], respectively, in excellent agreement with high-resolution frequency-resolved data. © 2001 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Manganese complexes exhibit a rich redox chemistry, usually accompanied by structural reorganization during the redox processes often followed by ligand dissociation or association. The push–pull ligand 2,6-diguanidylpyridine (dgpy) stabilizes manganese in the oxidation states +II, +III, and + IV in the complexes [Mn-(dgpy)2]n+ (n = 2–4) without change in the coordination sphere in the condensed phase [Heinze et al., Inorganic Chemistry, 2022, 61, 14616]. In the condensed phase, the manganese-(IV) complex is a very strong oxidant. In the present work, we investigate the stability and redox activity of the MnIV complex and its counterion (PF6–) adducts in the gas phase, using two modified 3D Paul ion trap mass spectrometers. Six different cationic species of the type [Mnx(dgpy)2(PF6)y]n+ (x = II, III, IV, y = 0–3, n = 1–3) could be observed for the three oxidation states MnIV, MnIII, and MnII, of which one observed complex also contains a reduced dgpy ligand. MnII species showed the highest relative stability in collision induced dissociation and UV/vis photo dissociation experiments. The lowest stability is observed in the presence of one or more counterions, which correlates to a lower total charge n+. Gas phase UV/vis spectra show similar features as the condensed phase spectra only differing in relative band intensities. The strongly oxidizing MnIV complex reacts with triethylamine (NEt3) in the gas phase to give MnIII, while MnIII species show little reactivity toward NEt3. [ABSTRACT FROM AUTHOR]

A high-resolution rotational coherence spectroscopy (RCS) investigation of para-cyclohexylaniline (pCHA) was performed using the methods of time-resolved stimulated Raman-induced fluorescence depletion (TRSRFD) and time-resolved stimulated emission pumping (TRSEP). TRSRFD and TRSEP are sensitive to ground state or excited state rotational constants, respectively and allow the deconvolution of the time-resolved fluorescence depletion (TRFD) spectrum to which both ground state and excited state rotational constants contribute. Moreover, from a detailed analysis of the presented experimental data it is deduced, that photoionization and internal vibrational relaxation (IVR)--not included in the picture of TRSEP, TRSRFD and TRFD--also contribute to the RCS spectra. The obtained rotational constants are in very good agreement with our previous high-resolution TRFD investigation of pCHA, allowing additionally for the unambiguous assignment of the excited state J-type transients. From a linear regression analysis of 25 transient positions (B+C)[sup ′]=719.74(53) MHz was calculated, confirming set (II) of our former investigation [C. Riehn, A. Weichert, U. Lommatzsch, M. Zimmermann, and B. Brutschy, J. Chem. Phys. 112, 3650 (2000)]. © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]

A high-resolution rotational coherence spectroscopy (RCS) investigation of para-cyclohexylaniline (pCHA) was performed with a solid-state picosecond laser setup, which allowed for the determination of rotational constants with unprecedented precision for a RCS experiment. The technique of time-resolved fluorescence depletion was used for the RCS measurements. The unique structural features of pCHA enabled the determination of both ground and excited state rotational constants. Three different sets of recurrences were observed in the spectrum and assigned to K[sup ″]-, K[sup ′]-, and J[sup ″]-type transients. From a detailed analysis by a grid search procedure based on the numerical simulation of RCS spectra and a nonlinear least-squares fitting routine the following rotational constants for the ground state were obtained: A[sup ″]=2406.5±0.6 MHz, (B+C)[sup ″]=714.9±0.4 MHz. For the electronic excited state two different sets of constants were found to fit the experimental data within the reported uncertainties: set (I) A[sup ′]=2343.6±1.3 MHz, (B+C)[sup ′]=714.4±1.7 MHz and set (II) A[sup ′]=2346.3±1.3 MHz, (B+C)[sup ′]=719.3±2.1 MHz. From additional information set (II) was found preferable for the description of the excited state. Furthermore, the fluorescence lifetime and the alignment of the transition dipole moment in the molecular frame were obtained from the fit procedure. For a structural characterization of pCHA we performed ab initio calculations of the electronic ground and excited state using HF/6-31G(d) and CIS/6-31G(d) levels of theory, respectively. These results were compared with the experiments and used to investigate the dependence of the rotational constants on characteristic intramolecular coordinates. © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]

The novel photoswitchable ligand 3,3'‐Azobenz(metPA)2 (1) is used to prepare a [Cu2(1)2](BF4)2 metallocycle (2), whose photoisomerization was characterized using static and time‐resolved spectroscopic methods. Optical studies demonstrate the highly quantitative and reproducible photoinduced cyclic E/Z switching without decay of the complex. Accordingly and best to our knowledge, [Cu2(1)2](BF4)2 constitutes the first reversibly photoswitchable (3d)‐metallocycle based on azobenzene. The photoinduced multiexponential dynamics in the sub‐picosecond to few picosecond time domain of 1 and 2 have been assessed. These ultrafast dynamics as well as the yield of the respective photostationary state (PSSZ = 65 %) resemble the behavior of archetypical azobenzene. Also, the innovative pump‐probe laser technique of gas phase transient photodissociation (τ‐PD) in a mass spectrometric ion trap was used to determine the intrinsic relaxation dynamics for the isolated complex. These results are consistent with the results from femtosecond UV/Vis transient absorption (fs‐TA) in solution, emphasizing the azobenzene‐like dynamics of 2. This unique combination of fs‐TA and τ‐PD enables valuable insights into the prevailing interplay of dynamics and solvation. Both analyses (in solution and gas phase) and quantum chemical calculations reveal a negligible effect of the metal coordination on the switching mechanism and electronic pathway, which suggests a non‐cooperative isomerization process. [ABSTRACT FROM AUTHOR]

Time-resolved pump-probe photoelectron spectroscopy has been used to study the relaxation dynamics of gaseous [Pt2(μ-P2O5H2)4 + 2H]2- after population of its first singlet excited state by 388 nm femtosecond laser irradiation. In contrast to the fluorescence and phosphorescence observed in condensed phase, a significant fraction of the photoexcited isolated dianions decays by electron loss to form the corresponding monoanions. Our transient photoelectron data reveal an ultrafast decay of the initially excited singlet ¹A2u state and concomitant rise in population of the triplet ³A2u state, via sub-picosecond intersystem crossing (ISC). We find that both of the electronically excited states are metastably bound behind a repulsive Coulomb barrier and can decay via delayed autodetachment to yield electrons with characteristic kinetic energies. While excited state tunneling detachment (ESETD) from the singlet ¹A2u state takes only a few picoseconds, ESETD from the triplet ³A2u state is much slower and proceeds on a time scale of hundreds of nanoseconds. The ISC rate in the gas phase is significantly higher than in solution, which can be rationalized in terms of changes to the energy dissipation mechanism in the absence of solvent molecules. [Pt2(μ-P2O5H2)4 + 2H]2- is the first example of a photoexcited multianion for which ESETD has been observed following ISC. [ABSTRACT FROM AUTHOR]

Time-resolved pump-probe photoelectron spectroscopy has been used to study the relaxation dynamics of gaseous [Pt2(μ-P2O5H2)4 + 2H]2- after population of its first singlet excited state by 388 nm femtosecond laser irradiation. In contrast to the fluorescence and phosphorescence observed in condensed phase, a significant fraction of the photoexcited isolated dianions decays by electron loss to form the corresponding monoanions. Our transient photoelectron data reveal an ultrafast decay of the initially excited singlet ¹A2u state and concomitant rise in population of the triplet ³A2u state, via sub-picosecond intersystem crossing (ISC). We find that both of the electronically excited states are metastably bound behind a repulsive Coulomb barrier and can decay via delayed autodetachment to yield electrons with characteristic kinetic energies. While excited state tunneling detachment (ESETD) from the singlet ¹A2u state takes only a few picoseconds, ESETD from the triplet ³A2u state is much slower and proceeds on a time scale of hundreds of nanoseconds. The ISC rate in the gas phase is significantly higher than in solution, which can be rationalized in terms of changes to the energy dissipation mechanism in the absence of solvent molecules. [Pt2(μ-P2O5H2)4 + 2H]2- is the first example of a photoexcited multianion for which ESETD has been observed following ISC. [ABSTRACT FROM AUTHOR]

We report the binding geometries of the isomers that are formed when the hydrogen oxalate ((CO2)2H=HOx) anion attaches to dinuclear coinage metal phosphine complexes of the form [M1M2dcpm2(HOx)]+ with M=Cu, Ag and dcpm=bis(dicyclohexylphosphino)methane, abbreviated [MM]+. These structures are established by comparison of isomer‐selective experimental vibrational band patterns displayed by the cryogenically cooled and N2‐tagged cations with DFT calculations of the predicted spectra for various local minima. Two isomeric classes are identified that feature either attachment of the carboxylate oxygen atoms to the two metal centers (end‐on docking) or attachment of oxygen atoms on different carbon atoms asymmetrically to the metal ions (side‐on docking). Within each class, there are additional isomeric variations according to the orientation of the OH group. This behavior indicates that HOx undergoes strong and directional coordination to [CuCu]+ but adopts a more flexible coordination to [AgAg]+. Infrared spectra of the bare ions, fragmentation thresholds and ion mobility measurements are reported to explore the behaviors of the complexes at ambient temperature. [ABSTRACT FROM AUTHOR]

Chemical and spectroscopic characterization of the mononuclear photosensitizers [(DPEPhos)Cu(I)(MPyrT)]0/+ (CuL, CuLH) and their dinuclear analogues (Cu2L', Cu2L'H2), backed by (TD)DFT and high‐level GW‐Bethe‐Salpeter equation calculations, exemplifies the complex influence of charge, nuclearity and structural flexibility on UV‐induced photophysical pathways. Ultrafast transient absorption and step‐scan FTIR spectroscopy reveal flattening distortion in the triplet state of CuLH as controlled by charge, which also appears to have a large impact on the symmetry of the long‐lived triplet states in Cu2L' and Cu2L'H2. Time‐resolved luminescence spectroscopy (solid state), supported by transient photodissociation spectroscopy (gas phase), confirm a lifetime of some tens of μs for the respective triplet states, as well as the energetics of thermally activated delayed luminescence, both being essential parameters for application of these materials based on earth‐abundant copper in photocatalysis and luminescent devices. [ABSTRACT FROM AUTHOR]

The modular synthesis of Au(I)/Ru(II) decorated mono‐ and heterobimetallic complexes with π‐conjugated [2.2]paracyclophane is described. [2.2]Paracyclophane serves as a rigid spacer which holds the metal centers in precise spatial orientations and allows metal‐to‐metal distance modulation. A broad set of architectural arrangements of pseudo ‐geminal, ‐ortho, ‐meta, and ‐para substitution patterns were employed. Metal‐to‐metal distance modulation of Au(I)/Ru(II) heterobimetallic complexes and the innate transannular π‐communication of the cyclophanyl scaffold provides a promising platform for the investigations of structure‐activity relationship and cooperative effects. The Au(I)/Ru(II) heterobimetallic cyclophanyl complexes are stable, easily accessible, and exhibit promising catalytic activity in the visible‐light promoted arylative Meyer‐Schuster rearrangement. [ABSTRACT FROM AUTHOR]

This article, titled "Cover Feature: A Photoswitchable Metallocycle Based on Azobenzene: Synthesis, Characterization, and Ultrafast Dynamics," highlights the discovery of an azobenzene-based metallocycle that can undergo reversible photoisomerization without disassembly. The cover feature showcases the switching between the (E,E) and (Z,Z) isomers of [Cu2(3,3'‐azobenz(metPA)2](BF4)2. The researchers used femtosecond UV/Vis transient absorption in solution and femtosecond pump-probe photodissociation in the gas phase to study the primary switching dynamics. For more information, readers can refer to the Research Article by C. Riehn, R. Diller, S. Becker, and their colleagues. [Extracted from the article]

The photoexcitation of a triangular silver(I) hydride complex, [Ag3(μ3‐H)(μ2‐dcpm)3](PF6)2 ([P](PF6)2, dcpm=bis(dicyclohexylphosphino)methane), designed with "UV‐silent" bis‐phosphine ligands, provokes hydride‐to‐Ag3 single and double electron transfer. The nature of the electronic transitions has been authenticated by absorption and photodissociation spectroscopy in parallel with high‐level quantum‐chemical computations utilizing the GW method and Bethe–Salpeter equation (GW‐BSE). Specific photofragments of mass‐selected [P]2+ ions testify to charge transfer and competing pathways resulting from the unique [Ag3(μ3‐H)]2+ scaffold. This structural motif of [P](PF6)2 has been unequivocally verified by 1H NMR spectroscopy in concert with DFT and X‐ray diffraction structural analysis, which revealed short equilateral Ag–Ag distances (dAgAg=3.08 Å) within the range of argentophilic interactions. The reduced radical cation [P].+ exhibits strong oxophilicity, forming [P+O2].+,which is a model intermediate for silver oxidation catalysis. [ABSTRACT FROM AUTHOR]

Abstract: The hybrid ligand 3‐(2,2′‐bipyridine‐6‐ylmethyl)‐1‐mesityl‐1H‐imidazolylidene (NHCBipy) featuring both carbene and N‐donor sites, was selectively complexed with various d10 metal cations in order to examine its coordination behavior with regard to homo and heterometallic structures. Respective silver complexes can be obtained by the silver oxide route and are suitable transmetallation reagents for the synthesis of gold(I) compounds. Starting from the mononuclear complexes [(NHCBipy)AuCl], [(NHCBipy)Au(C6F5)] and [(NHCBipy)2Au][ClO4], open‐chain as well as cyclic heterobimetallic complexes containing Cu+, Ag+, Zn2+, Cd2+, and Hg2+ were synthesized. Furthermore, the homobimetallic species [(NHCBipy)2M2][ClO4]2 (M=Cu, Ag) were obtained. All bimetallic compounds were fully characterized including single‐crystal X‐ray analysis. Their photoluminescence (PL) properties were investigated in the solid state at temperatures between 15 and 295 K and compared with those of the mononuclear species. There is a clear difference in PL properties between the open chain and the cyclic heterobimetallic complexes. The latter species show different PL properties, depending on the metals involved. In addition, collision‐induced dissociation (CID) experiments were performed on electrosprayed cations of the cyclic heterobimetallic compounds, to compare the metal binding at the carbene and N‐donor sites. [ABSTRACT FROM AUTHOR]

This study elucidates structures, activation barriers, and the gas-phase reactivity of cationic ruthenium transfer hydrogenation catalysts of the structural type [(η6-cym)RuX(pympyr)]+. In these complexes, the central ruthenium(+II) ion is coordinated to an η6-bound p-cymene (η6-cym), a bidentate 2-R-4-(2-pyridinyl)pyrimidine ligand (pympyr) with R = NH2 or N(CH3)2, and an anion X = I-, Br-, Cl-, or CF3SO3-. We present infrared multiple-photon dissociation (IR-MPD) spectra of precursors (before HCl loss) and of activated complexes (after HCl loss), which elucidates C-H activation as the key step in the activation mechanism. A resonant two-color IR-MPD scheme serves to record several otherwise "dark" bands and enhances the validity of spectral assignments. We show that collision-induced dissociation (CID)-derived activation energies of the [(η6-cym)RuX(pympyr)]+ (R = N(CH3)2) complexes depend crucially on the anion X. The obtained activation energies for the HX loss correlate well with quantum chemical activation barriers and are in line with the HSAB concept. We further elucidate the reaction of the activated complexes with D2 under single-collision conditions. Quantum mechanical simulations substantiate that the resulting species represent analogues for hydrido intermediates formed after abstraction of H+ and H- from isopropanol, as postulated for the catalytic cycle of transfer hydrogenation by us before. [ABSTRACT FROM AUTHOR]

We present a proof of concept that ultrafast dynamics combined with photochemical stability information of molecular photocatalysts can be acquired by electrospray ionization mass spectrometry combined with time-resolved femtosecond laser spectroscopy in an ion trap. This pump-probe 'fragmentation action spectroscopy' gives straightforward access to information that usually requires high purity compounds and great experimental efforts. Results of gas-phase studies on the electronic dynamics of two supramolecular photocatalysts compare well to previous findings in solution and give further evidence for a directed electron transfer, a key process for photocatalytic hydrogen generation. [ABSTRACT FROM AUTHOR]

We present a proof of concept that ultrafast dynamics combined with photochemical stability information of molecular photocatalysts can be acquired by electrospray ionization mass spectrometry combined with time-resolved femtosecond laser spectroscopy in an ion trap. This pump-probe 'fragmentation action spectroscopy' gives straightforward access to information that usually requires high purity compounds and great experimental efforts. Results of gas-phase studies on the electronic dynamics of two supramolecular photocatalysts compare well to previous findings in solution and give further evidence for a directed electron transfer, a key process for photocatalytic hydrogen generation. [ABSTRACT FROM AUTHOR]

We report on the first gas phase study of dianionic species [Pt 2 (μ-P 2 O 5 H 2 ) 4 + X,Y] 2− (X,Y = H, K, Ag) derived by counterion attachment to the dimetallic [Pt 2 (μ-P 2 O 5 H 2 ) 4 ] 4− complex (abbrev. Ptpop). The combined electrospray ionization mass spectrometry and laser spectroscopy investigation provides intrinsic properties and fragmentation pathways without solvent interaction in comparison to calculations by density functional theory (DFT) methods. Drastic differences between collision induced (loss of water) and UV photo-induced fragmentation (electron photodetachment or loss of Ag 0 ) in a quadrupole ion trap are observed. The underlying fragmentation pathways are explored in detail by MS n . Upon UV photoexcitation [Ptpop + H,Ag] 2− and [Ptpop + 2Ag] 2− exhibit dissociation of Ag 0 indicating an intramolecular electron transfer, whereas mainly electron photodetachment is observed for [Ptpop + 2H] 2− and [Ptpop + H,K] 2− . Channel specific photo-induced dissociation spectra in the range of 250–400 nm reveal the main band at ∼370 nm in remarkable resemblance to aqueous absorption spectra. Additional absorption features, distinct broadening and spectroscopic shifts depending on counterions and fragment channels are also observed. For the ground state structures a side-on coordination of metal counterions to the [Pt 2 (μ-P 2 O 5 H 2 ) 4 ] 4− framework is deduced based on fragmentation pathways, results of geometry optimizations and calculated absorption spectra. [ABSTRACT FROM AUTHOR]

The Schiff base compound 2,2'-{[(2-aminoethyi)imino]bis[2,l-ethanediyl-nitriloethylidyne]}bis-2- hydroxy-benzoic acid (H4L) as a proligand was prepared in situ. This proligand has three potential coordination pockets which make it possible to accommodate from one to three metal ions allowing for the possible formation of mono-, di-, and trinuclear complexes. Reaction of in situ prepared H4L with Dy(N03)-(-5H20 resulted in the formation of a mononuclear complex [Dy(H3L)2](N03)-(EtOH)-8(H20) (1), which shows SMM behavior. In contrast, reaction of in situ prepared H4L with Mn(C104)2-6H20 and Dy- (N03)3-5H20 in the presence of a base resulted in a trinuclear mixed 3d-4f complex (NHEt3)2[Dy{Mn(L)}2](Cl04)-2(H20) (2). At low temperatures, compound 2 is a weak ferromagnet. Thus, the SMM behavior of compound I can be switched off by incorporating two Mn(n) ions in close proximity either side of the Dy(lll). This quenching behavior is ascribed to the presence of the weak ferromagnetic interactions between the Mn(ll) and Dy(lll) ions, which at T > 2 K act as a fluctuating field causing the reversal of magnetization on the dysprosium ion. Mass spectiometric ¡on signals related to compounds 1 and 2 were bothdetected in positive and negative ion modes via electrospray ionisation mass spectrometry. Hydrogen/deuterium exchange (HDX) reactions with ND3 were performed in a FT-ICR Penning-trap mass spectrometer. [ABSTRACT FROM AUTHOR]

Invited for the cover of this issue are the research groups of Rolf Diller, Gereon Niedner‐Schatteburg, Christoph Riehn and Werner R. Thiel from the TU Kaiserslautern (TUK) and the group of Wim Klopper of the Karlsruhe Institute of Technology (KIT) collaborating within the research center "3MET" (SFB/TRR 88). The image depicts the photoinitiated charge transfer within a phosphine‐stabilized triangular silver hydride complex. Read the full text of the article at 10.1002/chem.201901981. [ABSTRACT FROM AUTHOR]

Highlights from the article: Keywords: charge transfer; hydride ligands; mass spectrometry; metal-metal interactions; photochemistry; silver The unique [Ag SB 3 sb ( SB 3 sb -H)] SP 2+ sp scaffold, featuring argentophilic interaction, was unequivocally verified by SP 1 sp H NMR spectroscopy in concert with X-ray structural analysis and DFT. Photochemistry, mass spectrometry, silver, charge transfer, hydride ligands, metal-metal interactions.

The article focuses on a study that investigates gas phase molecular clusters formed in supersonic beams at ultralow temperature. It is informed that IR/UV double resonance spectroscopy combining IR predissociation with UV resonant two-photon ionization and mass spectrometric detection makes it feasible for the selection of species out of a distribution of clusters differing in size and structure.