160Tb nuclear orientation in yttrium single crystal

First experimental results of¹⁶⁰Tb nuclear orientation in yttrium single crystal matrix are described. The influence of external magnetic field in combination with the crystal field interaction is discussed.     

56,57,60CoFe NMR/ON,hyperfine anomalies and γ-factors of cobalt isotopes

The results of NMR/ON measurements on^56'57'60Co isotopes in iron are presented. To avoid the uncertainties caused by local demagnetizing field inhomogenities the measurements on two cobalt isotopes in one sample have been carried out. The values of nuclear-factor ratios ⁵⁷/ ⁶⁰ = 1.805 (20), ⁶⁰/ ⁵⁶ = 0.761 (20), ⁵⁶/ ⁵⁷ = 0.726 (20) and hyperfine anomalies⁵⁶⁶⁰ = -0.036 (10),^{60 57} = 0.017 (10) and⁵⁷⁵⁶ = 0.018 (10) have been calculated from the experimental results.     

Many-body effects in nuclei

A correction to nuclear structure calculations due to the finite lifetime of the excited states of a nucleus entails many-body effects of different nature. The analytical structure, as well as the results of numerical calculations, are given and discussed.Presented at the symposium Mesons and Light Nuclei, Bechyn, Czechoslovakia, May 27–June 1, 1985.     

Hyperfine anomalies and nuclear γ-factors of56Co,57Co and60Co isotopes studied by NMR/ON

The results of NMR/ON measurements on^56,57,60Co isotopes in iron are presented in the paper. To avoid the uncertainties caused by local demagnetizing field inhomogeneities the measurements on two cobalt isotopes in one sample have been carried out. The values of nuclear-factors ratios ⁵⁷/ ⁶⁰=1·805(20), ⁶⁰/ ⁵⁶ = 0·761(20), ⁵⁶/ ⁵⁷ = 0·726(20) and hyperfme anomalies^{56 60} = –0·036(10),^{60 57} = 0·017(10) and^{57 56} = 0·018(10) have been calculated from the experimental results.Dedicated to the 30th anniversary of the Joint Institute for Nuclear Research.     

Darstellung und Kristallstruktur von Bis(heptaquocalcium)-dekachlorodithallat(III) [Ca(OH2)7]2TI2Cl10

Preparation and Crystal Structure of Bis(heptaquocalcium)-decachlorodithallat(III) [Ca(OH₂)₇]₂Tl₂Cl₁₀ Colourless, hygroscopic crystals of the compound CaTlCl₅ · 7H₂O were obtained by crystallization from aqueous solutions of CaCl₂ and TlCl₃. The crystal structure consists of [Ca(OH₂)₇]²⁺ cations and [Tl₂Cl₁₀]^4?anions.     

Investigation of an Open Quantum Mechanical System

The distinction between internal and external time is used in order to interpret the nuclear psics studies on the basis of the continuum shell model from the point of view of selforganization. A constraint operator consisting of a stochastic part and a dynamical part is defined. The interplay of both parts is investigated by means of numerical results obtained in the model. Conservative as well as dissipative structures in space and time are formed. Dissipative structures are characterized by a loss of information on the system while, simultaneously, information on the environment appears via the dynamical part of the constraint operator. The competition of structures is numerically investigated as well as the acceleration of improbable processes by the dynamical part. Irreversibility appears on a microscopic level.     

Antiferromagnetic Ordering in TmCu2

Intermetallic compound TmCu₂ crystalizes in the orthorhombic structure, orders antiferromagnetically (AF) and exhibits four different AF phases below T _N = 6.5 K. In all these phases the Tm magnetic moment is parallel to the b-axis. The ground-state AF1 (T < 3.4 K) corresponds to the squared-up AF structure with propagation vector ₀₁ = (5/8, 0, 0) and magnetic unit cell 8a × b × c. Narrow phases AF2 and AF3 (3.3 K < T < 3.7 K and 3.6 K < T < 4.6 K) are 'spin-slip'-derivatives from the AF1 structure, yielding propagation vectors ₀₂ = (0.633, 0, 0.02) and ₀₃ = (0.618, 0, 0), respectively. The phase AF4 (4.4 K < T < T _N) is then incommensurate transversal spin-wave with the propagation ₀₄ = (0.64, 0, 0). The co-existence of AF phases indicates the first-order transitions between them.