Bulk superconductivity and Pauli paramagnetism in nearly stoichiometric CuCo2S4

Triply Bonded Pancake π-Dimers Stabilized by Tetravalent Actinides

“…Compound 1-Th unexpectedly produced a small, temperature-independent paramagnetic contribution of approximately 2.6 × 10 −4 cm 3 mol −1 (Figure 3), reminiscent of the Pauli paramagnetism in electrically conductive solids. 66,67 The X-band EPR spectra of 1-Th and 1-U in the solid-state at 300 K displayed a small Lorentzian-shaped resonance centered on g-values of 2.0032 and 2.0036 (Figures 3, S19 and S20), respectively, accounting for approximately 2% of the sample (Figures S21−S26 and Supporting Information), and close to the free electron g-value.…”

“…The temperature dependence of the molar magnetic susceptibility (χ M ) was measured for 1-Th and 1-U in the solid state at temperatures in the range of 2–300 K. The susceptibility for 1-U is typical of uranium­(IV), with χ M increasing slightly from 0.016 cm 3 mol –1 at 300 K to 0.019 cm 3 mol –1 at 2 K, corresponding to μ eff values per uranium­(IV) center of 3.61 and 0.45 μ B , respectively (Figure ). Compound 1-Th unexpectedly produced a small, temperature-independent paramagnetic contribution of approximately 2.6 × 10 –4 cm 3 mol –1 (Figure ), reminiscent of the Pauli paramagnetism in electrically conductive solids. , The X-band EPR spectra of 1-Th and 1-U in the solid-state at 300 K displayed a small Lorentzian-shaped resonance centered on g -values of 2.0032 and 2.0036 (Figures , S19 and S20), respectively, accounting for approximately 2% of the sample (Figures S21–S26 and Supporting Information), and close to the free electron g -value. A variable-temperature EPR study at 80–300 K showed that the resonance increases in intensity with decreasing temperature, reminiscent of the conduction electron spin resonance reported for nanostructured graphite , and graphene. , …”