Photoelectron spectroscopy negative-ion

Dessent C E FI and Johnson M A 1998 Fundamentals of negative ion photoelectron spectroscopy Fundamentals and Applications of Gas Phase Ion Chemistry ed K R Jennings (Berlin Kluwer)... 

Lineberger W C 1982 Negative ion photoelectron spectroscopy Applied Atomic Collision Physics, Vol 5, Special Topics ed FI S W Massey, E W McDaniel and B Bederson (New York Academic)... 

Wenthold P and Lineberger W C 1999 Negative ion photoelectron spectroscopy studies of organic reactive intermediates Accts. Chem. Res. 32 597-604... 

In negative ion photoelectron spectroscopy (NIPES), the reactant is a negative ion, and the upper state is neutral. In this case, the origin can be used to determine the electron affinity. 

Figure 5.1. Schematic potential energy surfaces for the photoelectron spectroscopy experiment. Labels in parentheses refer to negative ion photoelectron spectroscopy.

In select cases, negative ion photoelectron spectroscopy can also be used to investigate reaction transition states.The ideal situation is illustrated in Figure... 

P. G. Wenthold and W. C. Lineberger, Negative Ion Photoelectron Spectroscopy Studies of Organic Reactive Intermediates, Acc. Chem. Res. 1999, 32, 597. 

The singlet-triplet splitting of NH was determined experimentally by spectroscopy of neutral NH and by negative ion photoelectron spectroscopy (PES) of the NH anion. In the latter experiment, the anion NH is prepared in the gas phase and exposed to monochromatic ultraviolet (UV)-laser hght. This photolysis leads to ejection of photoelectrons whose kinetic energies ( k) are analyzed. As the energy... 

Four of the most powerful methods presently applied to elucidate metal cluster geometric structure will be presented in the following. These are mass-selected negative ion photoelectron spectroscopy, infrared vibrational spectroscopy made possible by very recent advances in free electron laser (FEL) technology, gas-phase ion chromatography (ion mobility measurements), and rf-ion trap electron diffraction of stored mass-selected cluster ions. All methods include mass-selection techniques as discussed in the previous section and efficient ion detection schemes which are customary in current gas-phase ion chemistry and physics [71]. 

Ion cyclotron resonance (ICR) and flowing afterglow experiments can also be used to derive relative affinities. Neutral beam experiments, where a beam of alkali atoms such as Cs is crossed with a beam of molecules such as PCI3 or (012)2 have been used to derive thermochemistry for anions such as PCli" and Cli", but proper analysis of this type of data is difficult. High-resolution negative ion photoelectron spectroscopy (NIPES) experiments can provide otherwise unobtainable information on hypervalent anions, including precise electron affinities and vibrational frequencies.This technique has limited applicability to hypervalent species with more than three atoms because of vibrational congestion from low-frequency modes. 

To overcome this problem we recently suggested to correlate the ionization potential (IP) and the electron affinities (EA) of carbenes with the carbene philicity. [14] IP and EA of carbenes can in principle be measured by negative ion photoelectron spectroscopy (NIPES), and data of a series of simple carbenes and vinylidenes were published by Lineberger et al. [15-23] The experimental data allow to evaluate the reliability of theoretical methods for the calculation of IP and EA. As shown in Table 1, there is a decent agreement between the experimental EA and calculations of the vertical EA of carbenes. The calculated adiabatic EAs are systematically too large by ca. 0.3 eV. However, if the adiabatic EAs are corrected by this value the agreement with the experiment is even better. 

The aromaticity concept has been introduced to the chemistry literature through benzene and other cyclic molecules and their extension to inorganic molecules like borazine and silicazine. The seminal work of Boldyrev and coworkers has paved the way to have a recent upsurge of interest in the field of aromaticity and antiaromaticity of metal clusters (Fig. 13-17). Negative ion photoelectron spectroscopy using a laser vaporization source augmented by ab initio calculations have authenticated the aromatic nature... 

Calvi RMD, Andrews DH, Lineberger WC (2007) Negative ion photoelectron spectroscopy of copper hydrides. Chem Phys Lett 442 12-16... 

Hendricks, J. H.> Lyapustina, S. A.> de Clercq, H. L., Snodgrass, J. T., 8c Bowen, K. H. (1996). Dipole bound, nucleic acid base anions studied via negative ion photoelectron spectroscopy. The Journal of Chemical Physics, 104, 7788. 

W. Zheng, Negative ion photoelectron spectroscopy of metal clusters, metal-organic clusters, metal oxides, and metal-doped silicon clusters, 2005. 

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