# al-spam-echo_-5Q-selective-filtering-p1.in

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

# spin-5/2 echo amplitude optimization
# versus the first-pulse duration
# in three-pulse spam -5Q-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   20*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 {-5}
  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
# 2.83786981e-010 -1.01289174e-016
# 1.40611441e-007 -1.15953422e-016
# 5.11944722e-006 -3.49530683e-017
# 6.32019497e-005 1.5347465e-017
# 0.000427261326 4.14355862e-017
# 0.00195823428 -3.06017007e-017
# 0.00681986019 -5.25860778e-017
# 0.0193225289 -1.25700375e-017
# 0.0465516878 -7.3743205e-017
# 0.0983120906 -3.04807152e-017
# 0.186047289 3.01627934e-017
# 0.32074566 -1.17943465e-016
# 0.510274412 -3.05762335e-016
# 0.756883234 -5.16609327e-016
# 1.05563753 -1.11259932e-015
# 1.39426804 -7.24588207e-016
# END