title: Proton-detected 3D (14)N/(14)N/(1)H isotropic shift correlation experiment mediated through (1)H-(1)H RFDR mixing on a natural abundant sample under ultrafast MAS.
abstract: In this contribution, we have demonstrated a proton detection-based approach on a natural abundant powdered l-Histidine HCl-H2O sample at ultrafast magic angle spinning (MAS) to accomplish (14)N/(14)N correlation from a 3D (14)N/(14)N/(1)H isotropic shift correlation experiment mediated through (1)H finite-pulse radio frequency-driven recoupling (fp-RFDR). Herein the heteronuclear magnetization transfer between (14)N and (1)H has been achieved by HMQC experiment, whereas (14)N/(14)N correlation is attained through enhanced (1)H-(1)H spin diffusion process due to (1)H-(1)H dipolar recoupling during the RFDR mixing. While the use of ultrafast MAS (90kHz) provides sensitivity enhancement through increased (1)H transverse relaxation time (T2), the use of micro-coil probe which can withstand strong (14)N radio frequency (RF) fields further improves the sensitivity per unit sample volume.
authors.affiliation: RIKEN CLST-JEOL Collaboration Center, RIKEN, Yokohama, Kanagawa 230-0045, Japan.
authors.forename: Manoj Kumar
authors.initials: MK
authors.lastname: Pandey
authors.affiliation: RIKEN CLST-JEOL Collaboration Center, RIKEN, Yokohama, Kanagawa 230-0045, Japan; JEOL RESONANCE Inc., Musashino, Akishima, Tokyo 196-8558, Japan. Electronic address: yunishiy@jeol.co.jp.
authors.forename: Yusuke
authors.initials: Y
authors.lastname: Nishiyama
keywords: (1)H–(14)N HMQC; (14)N–(14)N correlation; Homonuclear correlation; Solid-state NMR; Ultrafast MAS