Search results for "SPIN STATES"
showing 10 items of 253 documents
HIGH SPIN STATES OF 232Th, 234U AND 236U+
1980
Quantum Spin-Tunneling:A Path Integral Approach
1995
We investigate the quantum tunneling of a large spin in a crystal field and an external magnetic field. The twofold degeneracy of the corresponding classical ground state is removed due to tunneling. The tunnel splitting ΔE o of the ground state is calculated by use of a path integral formalism. It is shown that coherent spin state path integrals do not yield a reasonable result. However a “bosonlzation” of the spin system yields excellent results in the semiclassical limit. This result follows from the coherent spin state approach from replacing the spin quantum number s by s + 1/2 which causes a renormalization of the preexponential factor of ΔE o .
Magnetic excitations in polyoxometalate tetrameric clusters
1997
Abstract The metal-oxide clusters with formula [M4(D2O)2(PW9O34)2]10− which contain a tetrameric magnetic cluster M4O16 provide an ideal series for the study of magnetic exchange interactions in polymetallic molecular clusters. To get a more direct information on the splitting of the spin states caused by the exchange interactions we have performed inelastic neutron scattering measurements on the Co, Mn and Ni clusters. Magnetic excitations have been observed in the range 0.5–6 meV. A tentative interpretation of these data from a Heisenberg exchange Hamiltonian and a single ion zero-field splitting is presented for Ni cluster.
The magnetic moment anomaly of the electron bound in hydrogen-like oxygen16O7
2003
The measurement of the g-factor of the electron bound in a hydrogen-like ion is a high-accuracy test of the theory of quantum electrodynamics (QED) in strong fields. Here we report on the measurement of the g-factor of the bound electron in hydrogen-like oxygen (16O7+). In our experiment a single highly charged ion is stored in a Penning trap. The electronic spin state of the ion is monitored via the continuous Stern?Gerlach effect in a quantum non-demolition measurement. Quantum jumps between the two spin states (spin up and spin down) are induced by a microwave field at the spin precession frequency of the bound electron. The g-factor of the bound electron is obtained by varying the micro…
Fundaments of photoelectric readout of spin states in diamond
2021
Abstract The chapter “Fundaments of photoelectric readout of spin states in diamond” deals with the detection of NV centre spins in diamond using the photoelectric detection of magnetic resonances (PDMR) method, introduced in a series of recent publications. It provides in particular insights into the physics of electronic transitions of the NV center, leading to the free carrier generation, and discusses methodologies how to implement the photocurrent detection principles in the dynamically evolving field of quantum technologies. Recent results on the single electron and the single nuclear spin qubits photoelectric readout are presented, along with a microwave-free NV magnetometry techniqu…
New features in systematics of low-spin states in even106?120Cd
1990
Low- spin states in even106–112Cd and116Cd were investigated by in-beam and off-beam γ-ray and conversion electron spectroscopy. New spin assignments and decay branching ratios for the levels in106Cd,108Cd and110Cd were obtained. From the new systematical data for the even106–120Cd, it is inferred that two sets of low-lying 0+ states cross between114Cd and116Cd. One of these sets appears to have features of both intruder and two-quadrupole-phonon states.
Spin Crossover, Liesst, and Niesst-Fascinating Electronic Games in Iron Complexes
1997
Abstract Coordination compounds of transition metal ions with open-shell electron configurations may exhibit dynamic electronic structure phenomena depending on the nature of the coordinating ligand sphere. The change of spin state with temperature (thermal spin crossover”) and light-induced electron transfer processes leading to long-lived metastable states are among the most fascinating electronic games encountered in transition metal compounds and are presently under intensive study by chemists and physicists. The first part of this lecture will survey briefly some highlights of previous work and present recent results on thermal spin crossover in iron(II) compounds. The second part of t…
Study of Intermediate-spin States of $^{98}$Y
2015
The nuclear structure of the odd–odd nucleus 98Y has been re-investigated by observing prompt γ rays emitted following the proton-induced fission of a 238U target, using the JUROGAM-II multidetector array. New highspin decays have been observed and placed in the level schemes using triple coincidences. The experimental level energies and γ-decay patterns are compared to GICM and QPRM calculations, assuming that this neutronrich N = 59 isotone is spherical at low energies and prolate deformed at intermediate spins. Web of Science 47 3 916 911
Spin Transition in Iron Compounds
1984
First-row transition metal complexes with d4 up to d7 electron configuration in octahedral ligand fields (and d8 electron configuration in six-coordinate complexes of lower symmetry) may undergo temperature dependent high spin (HS) ⇌ low spin (LS) transition, provided the ligand field strength (Δ), including low symmetry contributions, becomes comparable in magnitude with the mean spin pairing energy (P). At a critical field strength Δcrit = P, the energy levels of the two spin states cross. This is illustrated in Fig. 1, where a simplified Tanabe-Sugano type energy level diagram for d6 systems (e.g. Fe2+, Co3+) is shown as an example. For weak ligand fields, Δ Δcrit, the LS state1A1g(Oh) b…
High-spin states in the neutron-rich A∼100 region
2009
Two experimental setups have been used to study excited states of neutron‐rich nuclei in the A∼100 region. Extended level schemes and lifetime measurements were obtained using deep‐inelastic and fusion‐fission reactions with the CLARA‐PRISMA spectrometer and the Ge‐array GASP respectively. Experimental information from GASP has been used to complement the CLARA‐PRISMA experiment. Time spectra have been used to measure the lifetimes of isomeric states. Preliminary results are presented for 89Rb.