QMGreensite_merged
respect toIandS. This operator evolves under theJIRandJSRscalar coupling interactions but not under theJISscalar coupling intera ...
This operator represents multiple-quantum coherence (containing more than one transverse operator). The same result would be obt ...
durationt, Iycosð (^) ItÞþIxsinð (^) ItÞ! (^) IIzt Iycos^2 ð (^) ItÞIxcosð (^) ItÞsinð (^) ItÞ þIxsinð (^) ItÞcosð (^) ItÞþI ...
sequence is due to the scalar coupling interaction only. The initial 90x pulse generates the Iy operator from the equilibrium ...
Section 3.4.4), then the rf pulses in the spin echo sequence can be applied toonly oneof the scalar coupled spins (theIspins in ...
designed to perform specific tasks. An important experiment that takes advantage of the basic schemes is the INEPT (Insensitive ...
experiments. An additional advantage of the INEPT experiment, sometimes overlooked, is that the repetition rate of the experimen ...
refocused INEPT experiment ( 18 ) can now be written as Ispin: 90xt 180 xt 90 y 180 xdecouple, Sspin: 180 x 90 x ...
witht¼1/(4JIS), is called the spin-state-selective coherence transfer (S^3 CT) sequence element ( 19 ). The propagator correspon ...
The second line shows that the S^3 CT sequence selectively inverts the component ofSzmagnetization that is coupled to anIspin in ...
j i$j itransition is obtained by inverting the phase of the final y-pulse. The propagatorU¼exp(iI^ Sx) is obtained by shifting ...
does not affect the energy levels of the nuclear spin systems and consequently does not contribute to the observed resonance fre ...
TheF 2 qalso are the 2qþ1 components of an irreducible spherical tensor of second rank. With these definitions, the nuclear spin ...
T ABLE 2.4 Reduced Rotation Matrices (^2) dmn (^) ðÞ m ,n a 2 10 1 2 2 cos 4 = 2 ðÞ 12 sin cos þ 1 ðÞ ffiffiffiffiffiffif ...
of the Hamiltonian, with the result H¼^13 TrfgCuvþA^02 F 20 ðlabÞ ¼^13 TrfgCuvþA^02 X^2 k¼ 2 D^2 k 0 ðÞ (^) LP, (^) LP,0F 2 k ...
in whichp( , , ) is the probability distribution for the set of Euler angles { , , }. In isotropic solution, all molecular orien ...
In order to perform the averaging over the probability distribution, the principal axis system of the spin Hamiltonian must firs ...
in which the order parametersSmare defined as Sm¼ D^2 m 0 ðÞ (^) LA, (^) LA,0 , Sm¼ 1 mSm: ½ 2 : 319 The order parameters ...
in whichAkk¼(2/3)Skkare the principal values of the alignment tensor, Aa¼(3/2)Azzis the axial component of the tensor, andAr¼Axx ...
The potential energy function is ( 24 ) W¼ 1 2 0 BTB: ½ 2 : 329 Using similar derivations as used for the nuclear spin Ham ...
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