# al-spam-antiecho_-3Q-selective-filtering-p1.in

# approach: filtering the desired coherences (-3Q)  after the first pulse
#           and (±5Q, ±4Q, ±3Q, ±2Q, ±1Q, and 0Q) after the second pulse

# spin-5/2 antiecho amplitude optimization
# versus the first-pulse duration
# in three-pulse spam -3Q-MAS sequence,
# the second-pulse duration p2 = 4 micro seconds
# the third-pulse duration p3 = 2 micro seconds

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

par {
  spin_rate        5000
  variable tsw     0.25
  sw               1.0e6/tsw
  np               17
  crystal_file     rep10
  gamma_angles     10
  proton_frequency 800e6
  start_operator   12*I1z
  detect_operator  I1c
  verbose          1101
  variable rf      90000
  variable rf3     9300
  variable p2      4 
  variable p3      2 
}

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

  matrix set 1 coherence {-3}
  matrix set 2 coherence {9 8 7 6 5 4 3 2 1 0 -1 -2 -3 -4 -5 -6 -7 -8 -9}

  acq -y        
  for {set i 1} {$i < $par(np)} {incr i} {
    pulse $par(tsw) $par(rf) x
    store 2
    filter 1
    pulse $par(p2)  $par(rf) x
    filter 2
    pulse $par(p3) $par(rf3) -x
    acq -y
    reset
    prop 2
  }
}

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
# 2.5090573e-05 -1.52705103e-16
# 0.000794396294 -1.48548444e-16
# 0.00586083286 -2.43221487e-16
# 0.0235051986 -5.01520518e-16
# 0.0666833848 -6.25106211e-16
# 0.150254261 -8.57339975e-16
# 0.285861991 -6.84771963e-16
# 0.476395711 -6.24962579e-16
# 0.712890549 -5.34673947e-16
# 0.97607461 -3.82561123e-16
# 1.24250894 -1.8190331e-16
# 1.49266017 -3.65239786e-16
# 1.71699443 -1.13960296e-15
# 1.91718956 -1.45426656e-15
# 2.10221977 -1.41907623e-15
# 2.28168334 -5.26141498e-16
# END