# al-zfilter-phase-72-filtering-p3.in

# approach: filtering the desired coherence (+3Q) after the first pulse
#           and (0Q) after the second pulse

# spin-5/2 echo amplitude optimization
# versus the third-pulse duration
# in three-pulse z-filtered phase-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   72*I1z
  detect_operator  I1c
  verbose          1101
  variable rf      90000
  variable rf3     93000
  variable p1      4 
  variable p2      4 
}

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

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

  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
# -1.38704573 0.0269752131
# -4.46537649 0.0561536826
# -9.63638704 0.0859118532
# -15.7220987 0.11199559
# -20.7530325 0.129956046
# -23.0566598 0.136530685
# -21.9463147 0.129276527
# -17.8665962 0.107853442
# -12.1826821 0.0765652393
# -6.63683616 0.0439812989
# -2.54641759 0.0181330412
# -0.226709672 0.000694766776
# 0.931235762 -0.0136999478
# 1.82623261 -0.0315877115
# 2.9516261 -0.0544452678
# 4.11864597 -0.0771264293
# END