VSE knjižnice (vzajemna bibliografsko-kataložna baza podatkov COBIB.SI)
  • Double-quantum homonuclear correlation magic angle sample spinning nuclear magnetic resonance spectroscopy of dipolar-coupled quadrupolar nuclei
    Mali, Gregor, 1971- ; Fink, Gerhard ; Taulelle, Francis
    A double-quantum homonuclear correlation nuclear magnetic resonance experiments for dipolar-coupled half-ineteger quadrupolar nuclei in solids is presented. The experiment is based on rotary ... resonance dipolar recoupling and uses bracketed spin-lock pulses to excite double-quantum coherence and later to convert it to the zero=quantum one. A central-transition-selective pi pulseat the beginning of the t1 evolution period differentiates coherence transfer pathways of double-quantum coherences srising from coupled spins and from a single spin, so that the latter can be efficiently filtered out by phase cycling. The experiment was tested on an aluminophosphate molecular sieve AlPO4-14, a material with a variety of aluminium quadrupolar coupling constants, isotropic chemical shifts and homonuclear distances. In a two-dimensional spectrum aluminium dipolar couplings with internuclear distances between 2.9 and 5.5 A were resolved. Although the experiment requires an application of weak radio-frequency fields, frequency offsets did not affect its performance crucially.
    Vir: The Journal of chemical physics. - ISSN 0021-9606 (Vol. 120, no. 6, 2004, str. 2835-2845)
    Vrsta gradiva - članek, sestavni del
    Leto - 2004
    Jezik - angleški
    COBISS.SI-ID - 2978842