BABA 2rotations: 1D/2D double quantum excitation, 2 rotor period, BABA pulse program for TopSpin2.1

*** Outline ***

• Code for Avance III spectrometers with topSpin2.1 operating system
• Example: ³¹P in VPI-5 zeolite with AV500
• References

Code for Avance III spectrometers with topSpin2.1 operating system

;baba2rot (TopSpin 2.0)

;2D SQ-DQ correlation experiment for 2 rotor periods recoupling using BABA 
;for weaker dipole dipole interactions, e.g. 19F 
;compensated for pulse imperfections
;M. Feike, D.E. Demco, R. Graf, J. Gottwald, S. Hafner, and H.W. Spiess JMR A 122, 214-221 (1996)
;written by JOS, 11/12/03

;parameters:
;d1 : recycle delay
;d0 : incremented delay (2D) [1 usec]
;pl1 : for 90 degree BABA pulses
;p1 : 90 degree pulse (in BABA sequence and in presaturation sequence)
;l1 : number of rotor cycles for recoupling, any integer
;l2 : l2*2=l1=(number rotorcycles)
;d20 :delay between saturation pulses
;l20 : # of pulses in saturation pulse train, 0 if undesired
;cnst31 : rotation rate in Hz
;ns : n*16
;FnMode: States-TPPI or STATES

;$COMMENT=SQ-DQ correlation experiment with BABA for 2 rotor periods
;$CLASS=Solids
;$DIM=1D
;$TYPE=direct excitation
;$SUBTYPE=homonuclear correlation
;$OWNER=Bruker

define delay tau
  "tau=0.5s/cnst31-p1*2"

  "d0=1u"
  "in0=1s/cnst31"
  "l1=l2*2"
  "l0=2*l1"

;cnst11 : to adjust t=0 for acquisition, if digmod = baseopt
"acqt0=1u*cnst11"

  ze
1 d1

#ifdef presat                    ;set with -Dpresat
pres, d20                        ;delay between saturation pulses
  (p1 pl1 ph1):f1                ;saturation loop if required
  lo to pres times l20
#endif /* presat */

2 d1
5 (p1 pl1 ph12):f1               ;DQ excitation block
  tau
  (p1 ph12)
  (p1 ph13)
  tau
  (p1 ph14)
  (p1 ph12)
  tau
  (p1 ph12)
  (p1 ph14)
  tau
  (p1 ph13)
  lo to 5 times l2

  d0                             ;evolution of DQ coherence if more than 1 rotor period DQ excitation

7 (p1 ph23 ipp23)                ;DQ reconversion if more than one rotor period
                                 ;increment phase ph23 pointer
  tau
  (p1 ph23 ipp23)                ;increment phase ph23 pointer
  lo to 7 times l0

  (p1 ph6):f1
  go=2 ph31
  d1 mc #0 to 1 F1PH(ip12 & ip13 & ip14, id0)
HaltAcqu, 1m
exit


ph1= 0                           ;for saturation pulse

ph12=(8) 0 2 4 6                 ; x  y -x -y
ph13=(8) 2 4 6 0                 ; y -x -y  x
ph14=(8) 6 0 2 4                 ;-y  x  y -x
ph23= 0 0 1 3 0 0 3 1            ; x  x  y -y  x  x -y  y
ph6 = 0 0 0 0 1 1 1 1 2 2 2 2 3 3 3 3
ph31= 0 2 0 2 1 3 1 3 2 0 2 0 3 1 3 1