Low-energy spin dynamics in the<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:mo stretchy="false">[</mml:mo><mml:msub><mml:mtext>YPc</mml:mtext><mml:mrow><mml:mn>2</mml:mn></mml:mrow></mml:msub></mml:mrow></mml:math>]<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:msup><mml:mrow /><mml:mrow><mml:mn>0</mml:mn></mml:mrow></mml:msup></mml:mrow></mml:math><mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline">

Branzoli, Francesca; Carretta, P.; Filibian, Marta; Klyatskaya, Svetlana; Rüben, Mario

doi:10.1103/physrevb.83.174419

Cited by 22 publications

(25 citation statements)

References 22 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…An overview of the molecular orientation reported on various substrates can be found in Table 2. 42 For single-decker phthalocyanines, optical lab based methods, such as variable angle spectroscopic ellipsometry, were already many times successfully applied for the determination of the average molecular orientation on various substrates, including opaque substrates, and it was demonstrated that the results are in good agreement with synchrotron based methods like NEXAFS. These observations are in line with studies of planar phthalocyanine molecules on various metallic substrates, indicating that the interaction between the highest energetic occupied  orbital of the ligand and the substrate governs the molecular orientation of the first layer and the intermolecular interaction determines the orientation in thicker films.…”

Section: Molecular Orientation Of Tbpc 2 On Different Substratesmentioning

confidence: 99%

Tuning the magneto-optical response of TbPc₂ single molecule magnets by the choice of the substrate

et al. 2015

View full text Add to dashboard Cite

† Electronic supplementary information (ESI) available: Maldi-ToF spectrum of [TbPc2] 0 (Fig. S1). UV/vis/nIR spectrum of [TbPc2] 0 (Fig. S2). MOKE spectrum of a blank Si substrate (Fig. S3). VASE spectra of one sample and the model fit (Fig. S4), and in-plane components (Fig. S5), as well as the out-of-plane components of the dielectric tensor (Fig. S6) of the TbPc2 films grown on SiO2/Si. Complex refractive index of TbPc2/PTCDA (Fig. S7). Complex refractive index of TbPc2/Co (Fig. S8). Ligand field parameters of TbPc2 powder and film (Table S1).In this work, we investigated the magneto-optical response of thin films of TbPc2 on substrates which are relevant for (spin) organic field effect transistors (SiO2) or vertical spin valves (Co) in order to explore the possibility of implementing TbPc2 in magneto-electronic devices, the functionality of which includes optical reading. The optical and magneto-optical properties of TbPc2 thin films prepared by organic molecular beam deposition (OMBD) on silicon substrates covered with native oxide were investigated by variable angle spectroscopic ellipsometry (VASE) and magneto-optical Kerr effect (MOKE) spectroscopy at room temperature. The magneto-optical activity of the TbPc2 films can be significantly enhanced by one to two orders of magnitude when changing the molecular orientation (from nearly standing molecules on SiO2/Si substrates to nearly lying molecules on perylene-3,4,9,10-tetracarboxylic dianhydride (PTCDA) templated SiO2/Si substrates) or by using metallic ferromagnetic substrates (Co).

show abstract

Section: Molecular Orientation Of Tbpc 2 On Different Substratesmentioning

confidence: 99%

Tuning the magneto-optical response of TbPc₂ single molecule magnets by the choice of the substrate

et al. 2015

View full text Add to dashboard Cite

show abstract

“…On the basis of these results for the CF level splitting it is possible to analyze the temperature (T) dependence of muon spin-lattice relaxation rate in the presence of an applied field, derived from previous µSR measurements performed at the ISIS facility 12 and from new measurements performed at the Paul Scherrer Institute (PSI). Accordingly, the spinphonon couplings driving the transitions among the CF levels have been derived and the characteristic correlation time for the spin fluctuations estimated.…”

Section: Introductionmentioning

confidence: 99%

Spin and charge dynamics in[TbPc2]0and[
Branzoli
¹
,
Carretta
²
,
Filibian
³

et al. 2010
Phys. Rev. B
Self Cite
34
1
29
0
View full text Add to dashboard Cite

Magnetization, AC susceptibility and µSR measurements have been performed in neutral phthalocyaninato lanthanide ([LnPc2] 0 ) single molecule magnets in order to determine the low-energy levels structure and to compare the low-frequency spin excitations probed by means of macroscopic techniques, such as AC susceptibility, with the ones explored by means of techniques of microscopic character, such as µSR. Both techniques show a high temperature thermally activated regime for the spin dynamics and a low temperature tunneling one. While in the activated regime the correlation times for the spin fluctuations estimated by AC susceptibility and µSR basically agree, clear discrepancies are found in the tunneling regime. In particular, µSR probes a faster dynamics with respect to AC susceptibility. It is argued that the tunneling dynamics probed by µSR involves fluctuations which do not yield a net change in the macroscopic magnetization probed by AC susceptibiliy. Finally resistivity measurements in [TbPc2] 0 crystals show a high temperature nearly metallic behaviour and a low temperature activated behaviour.

show abstract

“…pNMR plays a central role in the elucidation of the quantum dynamics of single-molecule magnets and antiferromagnetic spin rings [3]. Moreover, it is an increasingly central technique for probing strong spin-orbit coupled electronic states in a dissipative environment, as shown by a recent study of quantum tunneling processes [4], silent in ac-susceptibility experiments, in lanthanide-based (Dy 3+ and Tb 3+ ) molecular nanomagnets.…”

mentioning

confidence: 99%

NMR Chemical Shift in an Electronic State with Arbitrary Degeneracy

2012

View full text Add to dashboard Cite

We present a theory of nuclear magnetic resonance (NMR) shielding tensors for electronic states with arbitrary degeneracy. The shieldings are here expressed in terms of generalized Zeeman (g (k) ) and hyperfine (A (k) ) tensors, of all ranks k allowed by the size of degeneracy. Contrary to recent proposals [T. O. Pennanen and J. Vaara, Phys. Rev. Lett. 100, 133002 (2008)], our theory is valid in the strong spin-orbit coupling limit. Ab initio calculations for the 4-fold degenerate Γ8 ground state of lanthanide-doped fluorite crystals CaF2:Ln (Ln = Pr 2+ , Nd 3+ , Sm 3+ , and Dy 3+ ) show that previously neglected contributions can account for more than 50% of the paramagnetic shift.Introduction. Paramagnetic nuclear magnetic resonance (pNMR) spectroscopy is a fundamental tool for probing static and dynamic local magnetic properties of materials [1] and metallo-proteins [2]. pNMR plays a central role in the elucidation of the quantum dynamics of single-molecule magnets and antiferromagnetic spin rings [3]. Moreover, it is an increasingly central technique for probing strong spin-orbit coupled electronic states in a dissipative environment, as shown by a recent study of quantum tunneling processes [4], silent in ac-susceptibility experiments, in lanthanide-based (Dy 3+ and Tb 3+ ) molecular nanomagnets.Despite the central role of pNMR in the development of new magnetic materials, only very recently ab initio approaches have been developed for the calculation of fundamental pNMR observables, such as nuclear shielding tensors [5]. In particular, by generalizing the work of Moon and Patchkovskii [6] on Kramers doublets, the paper by Pennanen and Vaara [7] stands out as the first comprehensive formulation of NMR shielding tensors in terms of molecular response properties, like the secondrank (first-rank in spin) EPR g and hyperfine A tensors, routinely computed via ab initio methods [5,[7][8][9][10]. The work by Pennanen and Vaara [7] aims at proposing an NMR-theory for arbitrary electronic ground state degeneracy. However, this task is only accomplished in [7] for the weak spin-orbit coupling limit, and to date no theory fully accounts for truly general (spin and orbital) electronic degeneracy, as that arising in strong spin-orbit coupled lanthanide nanomagnets.In this Letter we propose a general theory for the ab initio calculation of pNMR chemical shifts as function of molecular tensors of all ranks consistent with the size of degeneracy, which applies to arbitrarily strong spinorbit coupling (SOC) limit, and any degree of electronic degeneracy.Theory. In the linear response regime, the electroninduced magnetic field B I ind experienced by a nucleus I in a molecule immersed in a magnetic field B, is proportional to the field itself, so that B I ind = −B · σ I . This leads to an electron-mediated interaction energy between external field and the magnetic dipole moment µ I of nucleus I which is bilinear in the field and the nuclear

show abstract

Low-energy spin dynamics in the[YPc2]0

Cited by 22 publications

References 22 publications

Tuning the magneto-optical response of TbPc₂ single molecule magnets by the choice of the substrate

Tuning the magneto-optical response of TbPc₂ single molecule magnets by the choice of the substrate

Spin and charge dynamics in[TbPc2]0and[
Branzoli
¹
,
Carretta
²
,
Filibian
³

et al. 2010
Phys. Rev. B
Self Cite
34
1
29
0
View full text Add to dashboard Cite

NMR Chemical Shift in an Electronic State with Arbitrary Degeneracy

Contact Info

Product

Resources

About

Low-energy spin dynamics in the[YPc2]0

Cited by 22 publications

References 22 publications

Tuning the magneto-optical response of TbPc2 single molecule magnets by the choice of the substrate

Tuning the magneto-optical response of TbPc2 single molecule magnets by the choice of the substrate

Spin and charge dynamics in[TbPc2]0and[Branzoli1, Carretta2, Filibian3 et al. 2010Phys. Rev. BSelf Cite341290View full textAdd to dashboardCite

NMR Chemical Shift in an Electronic State with Arbitrary Degeneracy

Contact Info

Product

Resources

About

Tuning the magneto-optical response of TbPc₂ single molecule magnets by the choice of the substrate

Tuning the magneto-optical response of TbPc₂ single molecule magnets by the choice of the substrate

Spin and charge dynamics in[TbPc2]0and[
Branzoli
¹
,
Carretta
²
,
Filibian
³

et al. 2010
Phys. Rev. B
Self Cite
34
1
29
0
View full text Add to dashboard Cite