title: Phase cycling schemes for finite-pulse-RFDR MAS solid state NMR experiments.
abstract: The finite-pulse radio frequency driven dipolar recoupling (fp-RFDR) pulse sequence is used in 2D homonuclear chemical shift correlation experiments under magic angle spinning (MAS). A recent study demonstrated the advantages of using a short phase cycle, XY4, and its super-cycle, XY4(1)4, for the fp-RFDR pulse sequence employed in 2D (1)H/(1)H single-quantum/single-quantum correlation experiments under ultrafast MAS conditions. In this study, we report a comprehensive analysis on the dipolar recoupling efficiencies of XY4, XY4(1)2, XY4(1)3, XY4(1)4, and XY8(1)4 phase cycles under different spinning speeds ranging from 10 to 100 kHz. The theoretical calculations reveal the presence of second-order terms (T(10)T(2,±2), T(1,±1)T(2,±1), etc.) in the recoupled homonuclear dipolar coupling Hamiltonian only when the basic XY4 phase cycle is utilized, making it advantageous for proton-proton magnetization transfer under ultrafast MAS conditions. It is also found that the recoupling efficiency of fp-RFDR is quite dependent on the duty factor (τ180/τR) as well as on the strength of homonuclear dipolar couplings. The rate of longitudinal magnetization transfer increases linearly with the duty factor of fp-RFDR for all the XY-based phase cycles investigated in this study. Examination of the performances of different phase cycles against chemical shift offset and RF field inhomogeneity effects revealed that XY4(1)4 is the most tolerant phase cycle, while the shortest phase cycle XY4 suppressed the RF field inhomogeneity effects most efficiently under slow spinning speeds. Our results suggest that the difference in the fp-RFDR recoupling efficiencies decreases with the increasing MAS speed, while ultrafast (>60 kHz) spinning speed is advantageous as it recouples a large amount of homonuclear dipolar couplings and therefore enable fast magnetization exchange. The effects of higher-order terms and cross terms between various interactions in the effective Hamiltonian of fp-RFDR are also analyzed using numerical simulations for various phase cycles. Results obtained via numerical simulations are in excellent agreement with ultrafast MAS experimental results from the powder samples of glycine and l-alanine.
authors: Biophysics and Department of Chemistry, University of Michigan, Ann Arbor, MI 48109-1055, USA.
authors: Rongchun
authors: R
authors: Zhang
authors: JEOL RESONANCE Inc., Musashino, Akishima, Tokyo 196-8558, Japan; RIKEN CLST-JEOL Collaboration Center, RIKEN, Yokohama, Kanagawa 230-0045, Japan.
authors: Yusuke
authors: Y
authors: Nishiyama
authors: Key Laboratory of Functional Polymer Materials of Ministry of Education and College of Chemistry, Nankai University, Tianjin 300071, PR China.
authors: Pingchuan
authors: P
authors: Sun
authors: Biophysics and Department of Chemistry, University of Michigan, Ann Arbor, MI 48109-1055, USA. Electronic address: ramamoor@umich.edu.
authors: Ayyalusamy
authors: A
authors: Ramamoorthy
mesh_terms: D000465:Algorithms; D003198:Computer Simulation; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D008956:Models, Chemical; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012815:Signal Processing, Computer-Assisted
keywords: Dipolar recoupling; Phase cycling; RFDR; Solid-state NMR; Ultrafast MAS
references: J Am Chem Soc. 2012 Sep 12;134(36):14800-7
references: 22908968
references: J Chem Phys. 2008 Feb 7;128(5):052205
references: 18266410
references: Angew Chem Int Ed Engl. 2007;46(44):8380-3
references: 17907259
references: Chemphyschem. 2011 Apr 4;12(5):915-8
references: 21442705
references: J Magn Reson. 2014 Jun;243:25-32
references: 24713171
references: Angew Chem Int Ed Engl. 2013 Dec 23;52(52):14108-11
references: 24227750
references: J Magn Reson. 2014 Sep;246:79-93
references: 25093693
references: J Magn Reson. 2002 May;156(1):79-96
references: 12081445
references: J Am Chem Soc. 2012 Sep 12;134(36):14730-3
references: 22916960
references: Angew Chem Int Ed Engl. 2006 Jun 2;45(23):3878-81
references: 16646097
references: Angew Chem Int Ed Engl. 2012 Oct 22;51(43):10756-9
references: 23023570
references: J Magn Reson. 2008 Jul;193(1):89-93
references: 18462963
references: Acc Chem Res. 2013 Sep 17;46(9):2127-35
references: 23889329
references: Biophys J. 2014 Aug 19;107(4):941-6
references: 25140429
references: J Magn Reson. 2014 Feb;239:75-80
references: 24424008
references: Angew Chem Int Ed Engl. 2009;48(49):9322-5
references: 19894242
references: J Am Chem Soc. 2010 Apr 28;132(16):5558-9
references: 20356036
references: J Magn Reson. 2011 Sep;212(1):204-15
references: 21803622
references: J Magn Reson. 2012 May;218:115-27
references: 22449573
references: J Magn Reson. 2009 Dec;201(2):165-74
references: 19833538
references: J Magn Reson. 2014 Jul;244:1-5
references: 24801998
references: J Magn Reson. 2012 Mar;216:1-12
references: 22280934
references: J Biomol NMR. 2012 Nov;54(3):291-305
references: 22986689
references: Angew Chem Int Ed Engl. 2011 May 2;50(19):4508-12
references: 21495136
references: J Biomol NMR. 2013 Aug;56(4):379-86
references: 23812971
references: J Magn Reson. 2009 Jan;196(1):92-5
references: 18955001
references: Angew Chem Int Ed Engl. 2009;48(7):1253-6
references: 19130513
references: J Magn Reson. 2014 Jun;243:85-92
references: 24792960
references: J Magn Reson. 2015 Jan;250:37-44
references: 25486635
references: J Magn Reson. 2010 Jan;202(1):64-71
references: 19857977
references: Acc Chem Res. 2013 Sep 17;46(9):2089-97
references: 23745638
references: J Am Chem Soc. 2007 Sep 26;129(38):11791-801
references: 17725352
references: J Magn Reson. 2000 Dec;147(2):296-330
references: 11097821
references: J Biomol NMR. 2003 May;26(1):13-24
references: 12766399
references: J Am Chem Soc. 2003 Jul 2;125(26):7788-9
references: 12822982
references: J Magn Reson. 2010 Feb;202(2):135-9
references: 19900827
references: Solid State Nucl Magn Reson. 2014 Feb-Apr;57-58:17-21
references: 24287060
references: Proc Natl Acad Sci U S A. 2012 Jul 10;109(28):11095-100
references: 22723345
references: J Biomol NMR. 2004 Mar;28(3):229-33
references: 14752256
references: Chemphyschem. 2013 Sep 16;14(13):3131-7
references: 23589462
references: J Am Chem Soc. 2014 Sep 3;136(35):12489-97
references: 25102442
references: J Magn Reson. 2012 Oct;223:107-19
references: 22985981