Transition metal complexes with 2,6-Di-tert-butyl-p-quinone 1′-phthalazinylhydrazone

2,6-Di-tert-butyl-p-quinone 1′-phthalazinylhydrazone (HL) was synthesized. Quantum-chemical calculations of the energy of possible tautomeric forms of the hydrazone were performed. The complexes of Zn(II), Hg(II), Ni(II), and Cu(II) of ML₂ composition were obtained and studied. The structure of the NiL₂ complex was established by XRD. It was shown by DFT-D3 calculations that the cis-structure of the complex is stabilized due to the interligand dispersion interaction.     

Search for e + e − → f 0(600)γ, f 0(980)γ, f 0(1350)γ, and f 2(1270)γ processes in the energy range from 1.05 to 1.38 GeV

In the energy range from 1.05 to 1.38 GeV, the upper limits for the cross sections of e ⁺ e ^? → f ₀(600)γ, f ₀(980)γ, f ₀(1350)γ, and f ₂(1270)γ → π⁰π⁰γ processes have been established. Measurements are performed in accordance with the statistics gathered in experiment with a spherical neutral detector (SND) on the VEPP-2M e ⁺ e ^? collider. The resultant upper limits vary from 6 to 42 pb depending on the energy and the model.     

Certification of Control Gas Mixtures Using Modern Spectroscopy: an Approach and Application

The possibility of using the available spectroscopic databases for high-precision measurements of spectral parameters of gases has been studied. A new approach to measuring concentrations of gaseous components (НCl, CO, NO, SO₂) in gas mixtures employing the HITRAN or GEISA spectroscopic databases has been proposed. A certification method of control gas mixtures using Fourier-transform IR spectroscopy has been developed to transfer the mole-fraction units to working standards in order to reduce the required number of reference standards and improve the accuracy of measurements.     

Measurement of the ω, ρ → π0 e + e − branching fractions

The e ⁺ e ^? → ω, ρ → π⁰ e ⁺ e ^? processes have been investigated in the experiments with Spherical Neutral Detector at the VEPP-2M e ⁺ e ^? collider. The measurements provide the probability ?(ω → π⁰ e ⁺ e ^?) = (0.761 ± 0.053 ± 0.064) × 10^?3 of the ω → π⁰ e ⁺ e ^g- conversion decay and the upper limit ?(ρ → π⁰ e ⁺ e ^?) < 1.2 × 10^?5 (at 90% CL) for the ρ → π⁰ e ⁺ e ^? decay. The transition form factor was measured at three values of the 4-momentum transfer squared.     

The e + e −→π0π0γ process below 1.0 GeV

The e ⁺ e ^?→π⁰π⁰ γreaction was studied in the energy range 0.36–0.97 GeV on a VEPP-2M e ⁺ e ^? collider with an SND detector. The decay probabilities were found to be B(ω→ π⁰π⁰γ)= (7.8 ±2.7±2.0)×10^?5 and B(π→ π⁰π⁰γ)= (4.8 _?1.8 ^+3.4 ±0.2)×10^?5.     

Measurement of the cross section for the e + e ? → ωπ0 → π0π0γ process in the energy range of 1.1–1.9 GeV

The cross section for the e ⁺ e ^? ?? ???⁰ ?? ??⁰??⁰?? process has been measured in the energy range of 1.1?C1.9 GeV. The measurement has been made with the Spherical Neutral Detector at the VEPP-2000 e ⁺ e ^? collider. The data in the energy range of 1.1?C1.4 GeV are in agreement with the earlier measurements with the SND and CMD-2 detectors. The cross section has also been measured above 1.4 GeV.     

Investigations into beam monitors at the AEg ̄ IS experiment

Detailed diagnostic of antiproton beams at low energies is required for essentially all experiments at the Antiproton Decelerator (AD), but will be particularly important for the future Extra Low ENergy Antiproton ring (ELENA) and its keV beam lines to the different experiments. Many monitors have been successfully developed and operated at the AD, but in particular beam profile monitoring remains a challenge. A dedicated beam instrumentation and detector test stand has recently been setup at the AE \(\bar {g}\) IS experiment (Antimatter Experiment: Gravity, Interferometry, Spectroscopy). Located behind the actual experiment, it allows for parasitic use of the antiproton beam at different energies for testing and calibration. With the aim to explore and validate different candidate technologies for future low energy beam lines, as well as the downstream antihydrogen detector in AE \(\bar {g}\) IS, measurements have been carried out using Silicon strip and pixel detectors, a purpose-built secondary emission monitor and emulsions. Here, results from measurements and characterization of the different detector types with regard to their future use at the AD complex are presented.     

Tetranuclear Copper(II) Complex with N,N′-bis(2-N-Tosylaminobenzylidene)-1,3-Diaminopropan-2-ol: Crystal structure and magnetic properties

Tetranuclear copper(II) complex, [Cu₄L₂(OOCCH₂COO)], where L is triply deprotonated bis-N,N′-(2-N-tosylaminobenzylidene)-1,3-diaminopropan-2-ol, in which two binuclear fragments are linked by the malonate dianion, is synthesized. The exchange interaction in the binuclear clusters is shown to be antiferromagnetic (2J = ?59 cm^?1), whereas the intercluster interaction is ferromagnetic (zJ’ = 7.5 cm^?1). The structure of the DMSO solvate of the complex is determined by X-ray diffraction analysis.     

Effect of Coupling between Rotational and Translational Brownian Motions on NMR Spin Relaxation: Consideration Using Green Function of Rigid Body Diffusion

Using the Green function of arbitrary rigid Brownian diffusion (Goldstein,Biopolymers33, 409–436, 1993), it was analytically shown that coupling between translation and rotation diffusion degrees of freedom does not affect the correlation functions relevant to the NMR intramolecular relaxation. It follows that spectral densities usually used for the anisotropic rotation diffusion (Woessner,J. Chem. Phys.37, 647–654, 1962) can be regarded as exact in respect to the rotation–translation coupling for the spin system connected with a rigid body.