;1.8) Program: 	CSA filter (3-pulse version)
;Description: 	Selects alkyl (i.e. sp3-hybridized) C, e.g. O-C-O (which overlap with aromatic ;C) by three- or five-pulse CSA dephasing
;Requires: 	!; ca. 5 kHz MAS; short CP for O-CH-O selection; long CP & gated decoupling for ;O-Cq-O selection
;Reference(s):	Mao & KSR, Solid State NMR 26, 36-45 (2004); compare SUPER sequence (5.3) for ;measurement of all three CSA principal values


;srcsafilsp2A.simp
;(3-pulse version)
;from srcsafilsp2A.deph, simplified and only one p2 before Z filter
;gamma-integral before TOSS by l5-loop (set l5 = # of sidebands, 4 typically)
;TOtal Sideband Suppresion (TOSS) using four 180 13C pulses
;durations between 180 pulses (d25-d29) are calculated from l31 (=SS in Hz)
;pl2 is power level for contact, pl12 is power level for decoupling on F2

; set in6 to tr/l5 (e.g. tr/4), where l5 is the loop counter for the gamma integral

	
  "d25=(1s/l31)*0.1226-(p2/2)-2u-3u"
  "d26=(1s/l31)*0.0773-p2"   ;too short for power level switch
  "d27=(1s/l31)*0.2236-p2-6u"
  "d28=(1s/l31)*1.0433-p2-6u"
  "d29=(1s/l31)*0.7744-(p2/2)-3u-d13-d14"

  "l20=aq/(p8*2)"		;loop for tppm dec

1 ze
  10u pl1:f1		;preselect pl1 drive power level for F1
2 d1 do:f2		;recycle delay, turn the decoupler off

  10u pl2:f2		;preselect pl2 drive power for F2
  10u pl1:f1		;preselect pl1 drive power level for F1
  1u:f2 ph1
  1u:f1 ph2

  p3:f2 ph1		;proton 90 pulse
  (p15 ph2):f1 (p15 ph10):f2	;contact pulse

  1u cw:f2 pl12:f2 		;turn on F2 decoupling
  
    d21 pl11:f1		;tau of CSA dephasing (max. dephasing if d21 = tr/2)
  p2:f1 ph12	   	;180 pulse at tau 
    d21 		; refocus isotropic CS after this		

  p1:f1 ph7		;store for z-filter
    d6 do:f2		;z-filter & gamma integral
  1u cw:f2 		;turn on F2 decoupling
  1u pl12:f2		;set decoupling drive power level
  p1:f1 ph8	        ;read out

   d25                   ;
   3u pl22:f2
  p2:f1 ph3             ;180 13C #1
   d26                   ;
  p2:f1 ph4             ;180 13C #2
   3u pl12:f2
   d27                   ;
   3u pl22:f2
  p2:f1 ph5             ;180 13C #3
   3u pl12:f2
  d28                   ;
   3u pl22:f2
  p2:f1 ph6             ;180 13C #4
   3u pl12:f2
  d29                    ;
  d14 do:f2
  1u cpds2:f2 

  2u:f1 ph0       ;dead time delay, reset RF phase to detect
  
  go=2 ph31		;do NS scans
  1m do:f2; turn decoupler off
  id6			;increment d6 by in6=tr/4: gamma-average for clean TOSS
  lo to 2 times l5

;1D
  wr #0

14 dd6			;decrement d6 again
  lo to 14 times l5

exit

ph0= 0			        ;reference phase
ph1= 1 3			;1H 90
ph2= 0 0 1 1 2 2 3 3    ;13C CP
ph3= 1 1 2 2 3 3 0 0    ;180 13C #1 TOSS
ph4= 3 3 0 0 1 1 2 2    ;180 13C #2
ph5= 1 1 2 2 3 3 0 0    ;180 13C #3
     3 3 0 0 1 1 2 2
ph6= 2 2 1 1 0 0 3 3    ;180 13C #4
     0 0 3 3 2 2 1 1
ph7= 1 1 2 2 3 3 0 0   ;store for z-filter after t1
ph8= 3 3 0 0 1 1 2 2   ;read out after z-filter
ph10= 0			;1H CP

ph12= 0 	;180 at tau for csa filter, exorcycle

ph21= (360) 10			;TPPM first pulse
ph22= (360) 0			;TPPM second pulse

ph31= 0 2 3 1 2 0 1 3		;RLS with exorcycle (3 1 rather than 1 3)