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Determination of heisenberg exchange coupling constants in clusters with magnetic sites: A local spin approach
(John Wiley & Sons Inc, 2014-04)
This work studies the ability of the two-center local spin quantities, provided by the partitioning of the expectation value of the spin-squared operator math formula corresponding to N-electron systems, for determining ...
Transferência de estado quântico em cadeias de spin
(Universidade Federal do Rio Grande do NorteBrasilUFRNBacharelado em Física, 2017-10-07)
Quantum communication consists in transferring quantum states from one place to another. One of its most well known applications is quantum key distribution, in which a random secret key with security guaranteed by the ...
Determination of exchange coupling constants in linear polyradicals by means of local spins
(Springer, 2017-03)
This work extends the previously reported studies (Oliva et al. in Theor Chem Acc 132:1329, 2013, Theor Chem Acc 134:9, 2015) on electronic structures of simple polyhedral polyradicals constructed from s = ½ closo-carborane ...
Magnetic exchange couplings with range-separated hybrid density functionals
(American Chemical Society, 2010-06)
We investigate the effect of Hartree-Fock range-separation on the calculation of magnetic exchange couplings in a set of nine bimetallic transition-metal complexes containing 3d elements (V, Cr, Mn, and Cu). To this end, ...
Domain-wall profile in the presence of anisotropic exchange interactions: Effective on-site anisotropy
(American Physical SocCollege PkEUA, 2004)
Transições de fases quânticas em sistemas de spins em redes de baixa dimensionalidade
(Universidade Federal de Minas GeraisUFMG, 2015-11-13)
In this thesis we study spin systems in low dimension at zero temperature, analyzing their quantum phase transitions. In particular, we used a variational method and a linear spin wave theory for obtaining the approximate ...
Ferromagnetic bond of Li-10 cluster: An alternative approach in terms of effective ferromagnetic sites
(2016)
In this work, a model to explain the unusual stability of atomic lithium clusters in their highest spin multiplicity is presented and used to describe the ferromagnetic bonding of high-spin Li-10 and Li-8 clusters. The ...
Ground-state functional for quantum spin chains with bond defects
(AMER PHYSICAL SOC, 2010)
We have developed a nonlocal functional of the exchange interaction for the ground-state energy of quantum spin chains described by the Heisenberg Hamiltonian. An alternating chain is used to obtain the correlation energy ...