Photoelectron Spectroscopy of Nickel, Palladium, and Platinum Oxide Anions

The 364-nm negative ion photoelectron spectra of XO and OXO molecules (X=Ni, Pd, and Pt) are reported. The spectra yield the electron affinities (EAs): EA(NiO)=1.455±0.005 eV; EA(PdO)=1.672±0.005 eV; EA(PtO)=2.172±0.005 eV; EA(ONiO)=3.043±0.005 eV; EA(OPdO)=3.086±0.005 eV; EA(OPtO)=2.677±0.005 eV. In addition, for the diatomics, transitions from the anion X?²Π_3/2 and X?′²Π_1/2 states into neutral X?³Σ⁻, ³Π, and for NiO and PdO, ¹Π, are assigned. Several states have been reassigned from those in the existing literature. Anion ²Π_3/2-²Π_1/2 spin-orbit splittings are measured, as are neutral ³Π₂-³Π₁ spin-orbit splittings: the XO ³Π ₂-³Π₁ splittings increase from 405±30 cm⁻¹ (NiO) to 805±30 cm⁻¹ (PdO) to 3580±40 cm⁻¹ (PtO). A bond length shortening of 0.03±0.01 Å is measured upon electron detachment from NiO⁻, resulting in an anion bond length of 1.66±0.01 Å. The bond length does not change upon electron detachment from PdO⁻ using 3.4-eV photons. The Pt-O bond length decreases by 0.035±0.010 Å in the ³Π₁←²Π_3/2 transition. The spectrum of OPtO displays a significantly more extended vibrational progression than those of ONiO or OPdO, and the O-Pt bond length is found to decrease by 0.07±0.01 Å upon electron detachment. The spectra support the view that the Ni-O bond is largely ionic, the Pd-O bond is somewhat less so, and the Pt-O bond displays a substantial covalent character.     

Atomic-emission spectrum analysis of soil

A method of the atomic-emission spectrum analysis of soil has been developed for control of the accumulation of technogenic impurities in environmental objects. A sample, after calcination at 550°C, is evaporated in an arc discharge. Spectra are recorded by a DFS-8 spectrograph. Simultaneously, determination is made of Li, Ba, Sr, Cu, Zn, Cr, Ni, Co, Pb, Bi, Mo, V, Ge, Ga, Y, Nb, Sn, Cd. For the majority of the elements the detection limits are lower than their percent abundance in the crust and their maximum permissible concentrations. Institute for Single Crystals, National Academy of Sciences of Ukraine, 60, Lenin Ave., Khar'kov, 310001, Ukraine. Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 64, No. 3, pp. 396–399, May–June, 1997.     

X-Ray analysis of aqueous concentrates using organic glassy specimens

A simple and accessible method for the production of glassy specimens from aqueous concentrates based on saccharose is proposed. During the process of such a specimen preparation an additional concentration of impurities takes place. These saccharose specimens were used for the X-ray fluorescence determination of Se in waste water with crystallization preconcentration. Received: 17 July 1997 / Revised: 8 December 1997 / Accepted: 11 December 1997     

Pulsed laser deposition of PZT/Pt composite thin films with high dielectric constants

PbZr_0.53Ti_0.47O₃ (PZT) thin films containing nanoparticles of Pt (3–10 nm) were produced using pulsed laser deposition (PLD). The Pt content can be tuned by varying the energy density of the laser beam. Phase and microstructure analysis of the thin films was performed using XRD, SEM, TEM and AFM. The electrical properties were investigated by C–V and I–V measurements. The effective dielectric constant of the composite films increased substantially through the Pt dispersion. These films are promising candidates, for instance, for high-density dynamic random access memory (DRAM) devices. PACS 77.22.Ch; 77.84.Lf; 81.15.Fg     

A method for calculating the ground-state properties of light closed-shell nuclei

The He⁴ nucleus ground state is studied by means of the Goldstone perturbation theory. Explicit expressions for the binding energy up to the second order in the t-interaction and for expectation values of single-particle operators (mean square radius, mass and charge distribution) up to the first order are derived. The effects of the centre-of-mass motion of the whole nucleus are considered in detail, especially with respect to mass and charge distribution. The numerical results for the charge form factor and distribution confirm the deviation from the Gaussian model measured recently.The author thanks Professor I. Úlehla for interesting discussions and M. Plchová for technical assistance.