FIG. 6.1 C and R symmetry recoupling pulse sequences. (a) The generic construction of a C symmetry sequence. Each C sequence occupies N rotor periods, comprising n C blocks. Each C block consists of a π/2–2π–3π/2 pulse group, where the middle 2π pulse carries a π phase shift relative to the π/2 and 3π/2 pulses. A subsequent C block carries an increment ϕ = 2π/n phase shift to its prior C block. (b) The generic construction of an R symmetry sequence. Each R sequence occupies 2N rotor periods, comprising n R blocks. Each R block consists of a π–π pulse group, where the second π pulse carries a π phase shift relative to the first π pulse. A subsequent R block carries an increment ϕ = 2π/n phase shift to its prior C block. (c) The SPC5 sequence comprises two sets of C sequences, each with five standard 3-pulse C blocks occupying two rotor periods. (d) The original C7 sequence comprises seven groups of two pulse C blocks occupying two rotor periods. (e) An example of SPC5 for the excitation of double quantum correlation along indirect dimension. Here, note that higher decoupling is employed during SPC5 periods, to ensure optimal conversion efficiency. More about this image found in C and R symmetry recoupling pulse sequences. (a) The generic construction o...

FIG. 2.1 Schematic plot for the characteristic current vs voltage curve of typical diodes. The threshold and breakdown voltage values depend on the diode construction materials, and are not drawn to scale. More about this image found in Schematic plot for the characteristic current vs voltage curve of typical d...

FIG. 2.2 Quarter-wave cables and diodes are used in NMR circuit to achieve the desired impedance transformation between transmitter, probe, and receiver. (a) The voltage in the cable as a function of the length when the RF wavelength is comparable to the cable length. (b) Connection of cross-diode... More about this image found in Quarter-wave cables and diodes are used in NMR circuit to achieve the desir...