Electrophilic Properties of 2'-Deoxyadenosine···Thymine Dimer: Photoelectron Spectroscopy and DFT Studies.

The anion radical of the 2'-deoxyadenosine···thymine (dAT) pair has been investigated experimentally and theoretically in the gas phase. By employing negative-ion photoelectron spectroscopy (PES), we have registered a spectrum typical for the valence-bound anion, featuring a broad peak at the electron-binding energy (EBE) between ∼1.5 and 2.

Excess Electron Attachment to the Nucleoside Pair 2'-Deoxyadenosine (dA)-2'-Deoxythymidine (dT).

The 2'-deoxyadenosine···2'-deoxythymidine (dAdT(•-)) radical anion nucleoside pair has been investigated both experimentally and theoretically in the gas phase. The vertical detachment energy (VDE) and adiabatic electron affinity (AEA) were determined by anion photoelectron spectroscopy (PES). The measured photoelectron spectrum features a broad band having an onset at ∼1.

Photoelectron spectroscopy of boron aluminum hydride cluster anions.

Boron aluminum hydride clusters are studied through a synergetic combination of anion photoelectron spectroscopy and density functional theory based calculations. Boron aluminum hydride cluster anions, BxAlyHz(-), were generated in a pulsed arc cluster ionization source and identified by time-of-flight mass spectrometry. After mass selection, their photoelectron spectra were measured by a magnetic bottle-type electron energy analyzer.

The viability of aluminum Zintl anion moieties within magnesium-aluminum clusters.

Through a synergetic combination of anion photoelectron spectroscopy and density functional theory based calculations, we have investigated the extent to which the aluminum moieties within selected magnesium-aluminum clusters are Zintl anions. Magnesium-aluminum cluster anions were generated in a pulsed arc discharge source. After mass selection, photoelectron spectra of MgmAln (-) (m, n = 1,6; 2,5; 2,12; and 3,11) were measured by a magnetic bottle, electron energy analyzer.

Aluminum Zintl anion moieties within sodium aluminum clusters.

Through a synergetic combination of anion photoelectron spectroscopy and density functional theory based calculations, we have established that aluminum moieties within selected sodium-aluminum clusters are Zintl anions. Sodium-aluminum cluster anions, Na(m)Al(n)(-), were generated in a pulsed arc discharge source. After mass selection, their photoelectron spectra were measured by a magnetic bottle, electron energy analyzer.

Photoelectron spectroscopic and density functional theoretical studies of the 2'-deoxycytidine homodimer radical anion.

The intact (parent) 2'-deoxycytidine homodimer anion, (dC)2 (●-), was generated in the gas phase (in vacuo) using an infrared desorption∕photoemission source and its photoelectron spectrum was recorded using a pulsed, magnetic bottle photoelectron spectrometer. The photoelectron spectrum (PES) revealed a broad peak with the maximum at an electron binding energy between 1.6 and 1.

Photoelectron spectroscopy and density functional theory studies on the uridine homodimer radical anions.

We report the photoelectron spectrum (PES) of the homogeneous dimer anion radical of uridine, (rU)(2)(●-). It features a broad band consisting of an onset of ∼1.2 eV and a maximum at the electron binding energy (EBE) ranging from 2.

Photoelectron spectroscopy and computational modeling of thymidine homodimer anions.

The intact thymidine homodimer anion (dT(2)(-)) was generated in the gas phase using an infrared desorption/photoemission source and recorded by a pulsed photoelectron spectrometer. The photoelectron spectrum (PES) revealed a broad signal with the maximum at electron binding energy ∼2.0 eV and the threshold value at 1.

Evolution of superhalogen properties in PtCl(n) clusters.

We have systematically calculated the ground state geometries, relative stability, electronic structure, and spectroscopic properties of PtCl(n) (n = 1-7) clusters. The bonding in these clusters is dominated by covalent interaction. In neutral clusters, chlorine atoms are chemically bound to Pt up to n = 5.

Magnetic structure variation in manganese-oxide clusters.

Negative-ion photoelectron spectroscopy and ab initio simulations are used to study the variation in magnetic structure in Mn(x)O(y) (x = 3, 4[semicolon] y = 1, 2) clusters. The ferrimagnetic and antiferromagnetic ground-state structures of Mn(x)O(y) are 0.16-1.

Valence anions of N-acetylproline in the gas phase: computational and anion photoelectron spectroscopic studies.

We report the photoelectron spectrum of anionic N-acetylproline, (N-AcPro)(-), measured with 3.49 eV photons. This spectrum, which consists of a band centered at an electron binding energy of 1.

Photoelectron spectroscopic and computational studies of the Pt@Pb₁₀⁻¹ and Pt@Pb₁₂¹⁻/²⁻ anions.

A combination of anion photoelectron spectroscopy and density functional theory calculations has elucidated the geometric and electronic structure of gas-phase endohedral Pt/Pb cage cluster anions. The anions, Pt@Pb₁₀⁻¹ and Pt@Pb₁₂¹⁻ were prepared from "preassembled" clusters generated from crystalline samples of [K(2,2,2-crypt)]₂[Pt@Pb₁₂] that were brought into the gas phase using a unique infrared desorption/photoemission anion source. The use of crystalline [K(2,2,2-crypt)]₂[Pt@Pb₁₂] also provided access to K[Pt@Pb(n)](-) anions in the gas phase (i.

Joint photoelectron and theoretical study of (Rh(m)Co(n))⁻ (m=1-5, n=1-2) cluster anions and their neutral counterparts.

Anion photoelectron spectroscopic experiments and calculations based on density functional theory have been used to investigate and uniquely identify the structural, electronic, and magnetic properties of both neutral and anionic (Rh(m)Co(n)) and (Rh(m)Co(n))(-) (m=1-5, n=1-2) clusters, respectively. Negative ion photoelectron spectra are presented for electron binding energies up to 3.493 eV.

Photoelectron and computational studies of the copper-nucleoside anionic complexes, Cu(-)(cytidine) and Cu(-)(uridine).

The copper-nucleoside anions, Cu(-)(cytidine) and Cu(-)(uridine), have been generated in the gas phase and studied by both experimental (anion photoelectron spectroscopy) and theoretical (density functional calculations) methods. The photoelectron spectra of both systems are dominated by single, intense, and relatively narrow peaks. These peaks are centered at 2.

Photoelectron spectroscopic studies of 5-halouracil anions.

The parent negative ions of 5-chlorouracil, UCl(-) and 5-fluorouracil, UF(-) have been studied using anion photoelectron spectroscopy in order to investigate the electrophilic properties of their corresponding neutral halouracils. The vertical detachment energies (VDE) of these anions and the adiabatic electron affinities (EA) of their neutral molecular counterparts are reported. These results are in good agreement with the results of previously published theoretical calculations.

Electronic structure and properties of isoelectronic magic clusters: Al13X (X=H,Au,Li,Na,K,Rb,Cs).

The equilibrium structure, stability, and electronic properties of the Al(13)X (X=H,Au,Li,Na,K,Rb,Cs) clusters have been studied using a combination of photoelectron spectroscopy experiment and density functional theory. All these clusters constitute 40 electron systems with 39 electrons contributed by the 13 Al atoms and 1 electron contributed by each of the X (X=H,Au,Li,Na,K,Rb,Cs) atom. A systematic study allows us to investigate whether all electrons contributed by the X atoms are alike and whether the structure, stability, and properties of all the magic clusters are similar.

The anionic (9-methyladenine)-(1-methylthymine) base pair solvated by formic acid. A computational and photoelectron spectroscopy study.

The photoelectron spectrum for (1-methylthymine)-(9-methyladenine)...

Combined experimental and theoretical investigation of three-dimensional, nitrogen-doped, gallium cluster anions.

Anion photoelectron spectra of Ga(x)N(y)(-) cluster anions, in which x = 4-12, y = 1 and x = 7-12, y = 2, were measured. Ab initio studies were conducted on Ga(x)N(y)(-) cluster anions in which x = 4-7, y = 1 and Ga(7)N(2)(-), providing their structures and electronic properties. The photoelectron spectra were interpreted in terms of the computational results.

Photoelectron spectroscopy of homogeneous nucleic acid base dimer anions.

We report the photoelectron spectra of homogeneous dimer anions of the nucleobases: uracil, thymine, cytosine, adenine, and guanine, i.e., U(2)(-), T(2)(-), C(2)(-), A(2)(-), and G(2)(-) along with DFT calculations on U(2)(-) and T(2)(-).

Low-energy-barrier proton transfer induced by electron attachment to the guanine...cytosine base pair.

The photoelectron spectrum of the anion of the guanine...

Intrinsic neutral and anionic structures of glutathione.

Gas-phase intrinsic structures of intact neutral and anionic glutathione (GSH) have been determined by means of a combination of negative ion photo-electron spectroscopy and quantum chemistry calculations. The inferred structures of the neutral parents of those peptide anions are canonical (non-zwitterionic). These intrinsic structures are compared to those already known in aqueous solution or determined by crystallography in binding sites of enzymes.

Photoelectron spectroscopy of lanthanide-silicon cluster anions LnSi(n)(-) (3

Photoelectron spectroscopy was utilized to study a variety of LnSi(n)(-) cluster anions (Ln = Yb, Eu, Sm, Gd, Ho, Pr; 3 View Article and Find Full Text PDF

Valence anions of 9-methylguanine-1-methylcytosine complexes. Computational and photoelectron spectroscopy studies.

The photoelectron spectrum for the radical anion of 9-methylguanine-1-methylcytosine, MGMC(-), was recorded for the first time. To interpret the experimental results, B3LYP/6-31++G(d,p) level computational studies were carried out for the neutral and anionic complexes of MGMC/MGMC(-) stabilized by three hydrogen bonds and comprising canonical or low-energy tautomeric forms of the methylated nucleobases. The visualization of singly occupied molecular orbitals for the MGMC(-) anions indicates that they are valence-bound species since the excess electron is localized on a pi* orbital of cytosine.

Photoelectron spectroscopy of europium-silicon cluster anions, EuSin- (3

We report the photoelectron spectra of EuSi(n) (-) cluster anions (3 View Article and Find Full Text PDF