# al-zfilter-amplitude-selective-filtering-p3.in

# approach: filtering the desired coherences (-3Q and +3Q) after the first pulse
#           and (0Q, 4Q, and -4Q) after the second pulse

# spin-5/2 echo and antiecho amplitude optimization
# versus the third-pulse duration
# in three-pulse z-filtered amplitude-modulated 3Q-MAS sequence,
# the first-pulse duration p1 = 4 micro seconds
# the second-pulse duration p2 = 4 micro seconds

spinsys {
  channels 27Al
  nuclei   27Al
  quadrupole 1 2 3e6 0 0 0 0
}

par {
  spin_rate        5000
  variable tsw     0.25
  sw               1.0e6/tsw
  np               17
  crystal_file     rep100
  gamma_angles     10
  proton_frequency 800e6
  start_operator   24*I1z
  detect_operator  I1c
  verbose          1101
  variable rf      90000
  variable rf3     9300
  variable p1      4 
  variable p2      4 
}

proc pulseq {} {
  global par
  maxdt $par(tsw)

  matrix set 1 coherence {-3 3}
  matrix set 2 coherence {0 -4 4}

  acq -y        
  pulse  $par(p1) $par(rf) x
  filter 1
  pulse  $par(p2) $par(rf) x
  filter 2

  for {set i 1} {$i < $par(np)} {incr i} {
    pulse $par(tsw) $par(rf3) x 
    acq -y
  }
}

proc main {} {
  global par

  fsave [fsimpson] $par(name).fid
  puts "Larmor frequency (Hz) of 27Al: "
  puts [resfreq 27Al $par(proton_frequency)]
}

# SIMP
# NP=17
# SW=4000000
# TYPE=FID
# DATA
# 0 0
# -0.0705170464 4.29186068e-05
# -0.142311857 0.000173070046
# -0.216410879 0.000392589726
# -0.293427562 0.000701304522
# -0.373368988 0.00109432734
# -0.455533124 0.0015647185
# -0.538571654 0.00211006522
# -0.620698253 0.00273550463
# -0.700043991 0.00344984484
# -0.775035252 0.00425894721
# -0.844579828 0.00516158647
# -0.908059084 0.00615018764
# -0.965274766 0.00721520374
# -1.01640642 0.00834812536
# -1.06200315 0.00953959943
# -1.10302485 0.0107754704
# END