2013 **Abstract:** Pseudocontact shifts (PCS) contain a wealth of geometric information, which makes paramagnetic NMR one of the best methods for accurate geometric determinations in solution. It is well-known that PCS are intrinsically linked to Fermi contact (FC) shifts, and the separation of the two terms is achieved through linearization methods, which heavily rely on (a) isostructurality (even concerning a labile axial site) and (b) the validity of Bleaney's constants. Recently we proposed a method that circumvents both ass…

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“…As af urther bonus, Yb complexes are particularly suited forp aramagnetic NMR spectroscopy analysis. [22] The purpose of the presents tudy is to test Richardson's modela saway to calculate the fine structure of the l = 980 nm electronic circular dichroism multiplet of chiral Yb 3 + systems. The fallouto ft hese predictionsw ill be to better rationalize the fundamental chiroptical spectra of lanthanides, especially in connection with their use as luminescent materials.…”

confidence: 99%

“…As af urther bonus, Yb complexes are particularly suited forp aramagnetic NMR spectroscopy analysis. [22] The purpose of the presents tudy is to test Richardson's modela saway to calculate the fine structure of the l = 980 nm electronic circular dichroism multiplet of chiral Yb 3 + systems. The fallouto ft hese predictionsw ill be to better rationalize the fundamental chiroptical spectra of lanthanides, especially in connection with their use as luminescent materials.…”

confidence: 99%

“…Except for La 3+ , Gd 3+ , and Lu 3+ ions, all other Ln 3+ ions possess unpaired electrons and this paramagnetism induces remarkable shifts of nuclear resonances (Lanthanide Induced Shift or LIS effect) with respect to the diamagnetic terms (lutetium derivative in this study). In the principal system of Ln 3+ magnetic susceptibility tensor ( χ Ln ), under the assumption that the unpaired electron(s) cloud can be effectively described as a point (i.e., that the 4 f ‐electron radial distribution is small compared to the Ln‐H or Ln‐C distances), one can write well‐established relationships $${\delta}_{ij}^{\mathrm{exp}}={\delta}_{i}^{dia}+{\delta}_{ij}^{\mathsf{\text{para}}}={\delta}_{i}^{dia}+{\delta}_{ij}^{FC}+{\delta}_{ij}^{PCS}$$ $${\delta}_{ij}^{FC}=-\frac{{{\rm A}}_{i}}{\hslash}\frac{{\left({S}_{Z}\right)}_{j}}{{\gamma}_{I}{B}_{0}}={F}_{i}{\u27e8{S}_{Z}\u27e9}_{j}$$ $${\delta}_{ij}^{PCS}={D}_{I,j}\frac{3{\mathrm{cos}}^{2}{\theta}_{i}-1}{{r}_{i}^{3}}+{D}_{II,j}\frac{{\mathrm{sin}}^{2}{\theta}_{i}{\mathrm{sin}}^{2}{\mathrm{\Omega}}_{i}-1}{{r}_{i}^{3}}={D}_{I,j}{G}_{i}+{D}_{II,j}{H}_{i}$$ in which the index i ‐th refers to the considered resonant nucleus and the j ‐th index to the lanthanide; δ dia ij is the chemical shift in a reference diamagnetic compound ( j = La 3+ or Lu 3+ ); δ FC ij is the Fermi contact shift and δ PCS ij is the pseudocontact shift; A i / ħ is the hyperfine coupling constant; γ 1 is the gyromagnetic ratio of the observed nucleus and B 0 is the applied magnetic field; ⟨ S z ⟩ j is the expectation value of S z operator for the specific lanthanide; G i and H i are geometrical factors of the i ‐th nucleus, dependent on ( r i , θ i , Ω i ), its spherical coordinates in a polar system centered on the metal ion; D I , j and D II , j are respectively the axial and rhombic t...…”

confidence: 99%

“…Except for La 3+ , Gd 3+ , and Lu 3+ ions, all other Ln 3+ ions possess unpaired electrons and this paramagnetism induces remarkable shifts of nuclear resonances (Lanthanide Induced Shift or LIS effect) with respect to the diamagnetic terms (lutetium derivative in this study). In the principal system of Ln 3+ magnetic susceptibility tensor ( χ Ln ), under the assumption that the unpaired electron(s) cloud can be effectively described as a point (i.e., that the 4f-electron radial distribution is small compared to the Ln-H or Ln-C distances), one can write well-established relationships 16,18…”

confidence: 99%