Resonances in Three-Body Systems Studied by a Full Angular-Momentum, Smooth-Exterior Complex-Scaling Finite-Element Method

 The development of a tool for calculating resonances and bound states in three-body systems described by a single-potential energy surface is reported. The method has been applied to the antiprotonic helium, doubly excited states in helium, the ¹¹Li nuclear halo, the NeICl van der Waals molecule, and the recently found FHD reaction complex. Received November 26, 2001; accepted for publication November 28, 2001     

Synthesis, Crystal Structure Determination, and Physicochemical Study of the Nickel(II) Complex of 4-(Pyridyl-2)-1,2,4-triazole

A new trinuclear nickel(II) complex with 4-(pyridyl-2)-1,2,4-triazole (pytrz), [Ni₃(pytrz)₆(H₂O)₆](NO₃)₆, has been synthesized, and its crystal structure has been determined. The compound was studied by X-ray phase analysis (XRPA), magnetochemical measurements, and electronic and IR spectroscopy.     

Crystal structure of two complexes containing tris-(β-diketonato)magnate anion

Single crystal XRD is used to determine the structures of the complexes (H₂TMEDA)[Mg(ptac)₃]₂ (1, TMEDA = Me₂N(CH₂)₂NMe₂, ptac = ^t BuCOCHCOCF₃) and (H₂TMEDA)[Mg(hfac)₃](hfac) (2, hfac = CF₃COCHCOCF₃) at a temperature of 150 K. The crystallographic data for complex 1: a = 10.2919(3) Å, b = 10.9492(4) Å, c = 15.4159(6) Å, α = 87.117(1)°, β = 89.686(1)°, γ = 79,864(1)°, space group $P\bar 1$ Z = 1, R = 0.0573; for complex 2: a = 12.9446(2) Å, b = 23.0035(4) Å, c = 13.1473(3) Å, β = 98.779(1)°, space group P2₁/n, Z = 4, R = 0.0605. The structures are ionic; the metal atom coordinates six oxygen atoms of three β-diketonate ligands. The distances Mg-O in complex 1 are in the range 2.036(2)–2.0920(19) Å; the same distances in complex 2 are in the range 2.051(2)–2.076(2) Å. The spatial packing is determined by the system of hydrogen bonds between the (H₂TMEDA)²⁺ cations and [Mg(ptac)₃]^? (1) or hfac^? (2) anions. A thermogravimetric study of complex 1 is carried out.     

Nitrosoruthenium hydroxo and aqua complexes of the trans-dipyridine series: Synthesis,structures, and characterization

A procedure for the synthesis of trans-Ru(NO)(Py)₂Cl₂(OH) (I) from K₂[Ru(NO)Cl₅] was proposed. Treatment of hydroxo complex I with HCl or H₂SO₄ at room temperature gave the corresponding salts trans-[Ru(NO)(Py)₂Cl₂(H₂O)]Cl · 2H₂O (II) and trans-[Ru(NO)(Py)₂Cl₂(H₂O)]HSO₄ (III). All the complexes obtained were characterized by ¹H and ¹³C NMR and IR spectroscopy and elemental analysis; their structures were determined by X-ray diffraction. The structures are stabilized by π-stacking between the pyridine ligands of adjacent complex species.     

One-Dimensional Relativistic Problems on the Bound States and Degradation for a Superposition of Two δ Potentials

For a superposition of two potentials, exact one-dimensional wave functions of the bound states with quantization conditions and exact wave functions of the degradation state with transmission and reflection coefficients have been found. The phenomenon of complete reflection taking place for potentials of this type is investigated.     

Structure,synthesis, and thermal properties of trans-[Ru(NO)(NH3)4(SO4)]NO3·H2O

In treatment of trans-[Ru(NO)(NH₃)₄(OH)]Cl₂ with concentrated sulfuric acid on heating trans-[Ru(NO)(NH₃)₄(SO₄)](HSO₄)·H₂O (I) is obtained with a yield close to quantitative. In the interaction of the saturated solution of I with a saturated NaNO₃ solution a trans-[Ru(NO)(NH₃)₄(SO₄)]NO₃·H₂O (II) precipitate forms whose structure is determined by single crystal XRD: space group P2₁2₁2₁, a = 6.8406(3) Å, b = 12.6581(5) Å, c = 13.3291(5) Å. A monodentately coordinated sulfate ion is in the trans-position to the nitroso group. Compound II is characterized by IR spectroscopy, powder XRD, and diffuse reflectance spectroscopy. The process of its thermolysis is studied; by differential scanning calorimetry the thermal effect of the dehydration reaction occurring on heating to 120°C (ΔH = 58.9 ± 1.5 kJ/mol) is estimated. The final product of the thermolysis of II is a mixture of Ru and RuO₂.     

Analog of the frobenius method for solving homogeneous integral equations of the quasi-potential approach in a relativistic configurational representation

A method is suggested for constructing a solution of the homogeneous integral equation of a three-dimensional, covariant, simultaneous theory of bound states formulated in a relativistic configurational representation. The method is based on representing the unknown solutions in the form of a combination of functions that includes hyperbolic functions and polynomials (degenerate power series). Using this method and the REDUCE system of analytical calculations, the exact conditions determining the mass spectrum and the exact wave functions for a two-particle relativistic system with a quasi-potential [tanh(πr/2)]/r are found. F. Skorina State University, Gomel’. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 7, pp. 53–61, July, 1997.     

Single-photon exchange quasi-potentials ofN-particle systems

The covariant single-time approach of quantum field theory and perturbation theory are used to construct an explicit form of the electromagnetic interaction operator for mixedN-particle systems consisting of spinor and scalar particles. F. Skoriny State University, Gomelsk. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 9, pp. 13–25, September, 1997.     

Conformations of 1,1-phthaloyl-2-benzoylcyclopropanes

Conclusions The benzoyl group in 1,1-phthaloyl-2-benzoylcyclopropane and its derivatives deviates from s-cis conformation by 15–30° in a direction corresponding to the withdrawal of the carbonyl groups.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 4, pp. 782–784, April, 1981.     

Transition-metal bimaleates and their solid solutions: Synthesis,structural, and thermoanalytical study

Transition-metal hydrogen maleates of composition M(C₄H₃O₄)₂ · 4H₂O, where M = Mn, Fe, Co, and Ni, and their solid solutions were synthesized and characterized by X-ray crystallography, IR spectroscopy, mass spectrometry, and thermal analysis. X-ray crystallography and IR spectroscopy showed that both intramolecular and intermolecular H-bonds exist in these compounds. The generation of continuous substitutional solid solutions with cation substitution in these compounds was studied. The thermolysis mechanism was studied for both transition-metal hydrogen maleates and their solid solutions. The composite produced by thermolysis is stable up to 1200°C in flowing helium.