ENDOR investigations of the Ce3+ ions in YAG: Transferred hyperfine interaction with nearest aluminum ions

Abstract

The transferred hyperfine interactions of Ce3+ centers with 27Al neighbor nuclei in heavily cerium doped yttrium aluminum garnet (YAG) are resolved using Pulsed-Electron Nuclear Double Resonance (Pulsed-ENDOR). It is demonstrated that substitution of Ce3+ for Y3+ in YAG crystals leads to the strong reduction of the nuclear quadrupole coupling at the tetrahedral aluminum d-sites (e2qQ/h ≈ 4.67 MHz).

Metal Bonding with 3d and 6d Orbitals: An EPR and ENDOR Spectroscopic Investigation of Ti3+–Al and Th3+–Al Heterobimetallic Complexes

“…The field-dependent Davies ENDOR spectra of 1a in the low-frequency region (2–30 MHz) exhibit wide features that are attributed to the HFI and NQI of 27 Al ( I = 5 / 2 ; Figure ). Notably, at the “single-crystal-like” g 1 edge, the ENDOR peaks are uniformly spaced by the orientation-dependent NQI splitting, 3 P 1 = 3 MHz, representing a rare example of a well-resolved 27 Al ENDOR spectrum with a well-resolved NQI pattern. − The large NQI splitting cause an overlap between the two ENDOR branches. Similar patterns are seen at the g 3 edge with 3 P 3 ∼ 2 MHz.…”

“…Although there are two bridging hydrides in 1a, their HFI tensors are likely to be similar because of the presence of a pseudo mirror plane. Indeed, the outer region of the ENDOR spectra of 1a can be wellsimulated with one 1 H HFI tensor (Figure 2A, red trace) of A 1 H = [6.8, −15.2, −20.7] MHz with Euler angles of [63,3,0]°r elative to the g frame (Table 1). Decomposition of A gives an a iso of −9.7 MHz that is consistent with the value determined from CW EPR and an anisotropic component of T = [16.5, −5.5, −11.0] MHz.…”