Efficient Ab Initio Multiplet Calculations for Magnetic Adatoms on MgO.
Christoph WolfFernando DelgadoJosé ReinaNicolás LorentePublished in: The journal of physical chemistry. A (2020)
Scanning probe microscopy and spectroscopy, and more recently, single-atom electron spin resonance, have allowed the direct observation of electron dynamics at the atomic limit. The interpretation of data is strongly dependent on model Hamiltonians. However, fitting effective spin Hamiltonians to experimental data lacks the ability to explore a vast number of potential systems of interest. By using plane-wave density functional theory as starting point, we build a multiplet Hamiltonian making use of maximally localized Wannier functions. The Hamiltonian contains spin-orbit and electron-electron interactions needed to obtain the relevant spin dynamics. The resulting reduced Hamiltonian is solved by exact diagonalization. We compare three prototypical cases of 3d transition metals Mn (total spin S = 5/2), Fe (S = 2), and Co (S = 3/2) on MgO with experimental data and find that our calculations can accurately predict the spin orientation and anisotropy of the magnetic adatom. Our method does not rely on experimental input and allows us to explore and predict the fundamental magnetic properties of adatoms on surfaces.
Keyphrases
- density functional theory
- molecular dynamics
- electron microscopy
- single molecule
- high resolution
- electronic health record
- room temperature
- molecularly imprinted
- big data
- solar cells
- electron transfer
- data analysis
- deep learning
- staphylococcus aureus
- high speed
- cystic fibrosis
- climate change
- living cells
- quantum dots
- metal organic framework
- artificial intelligence
- molecular dynamics simulations
- visible light