AB Sciex 4500 Series System User's Manual page 51

Figure 5-1 Ion optics path and parameters (Continued)
Item Parameter
4 CXP (Collision
Cell Exit
Potential)
4 TDF CE (Time
Delayed
Fragmentation
Collision Energy)
5 Q3 Entry Barrier
5 Q3 Empty Time
MS/MS/MS
Fragmentation
Time
6 MCS (Multi-
Charge
Separation)
Barrier
6 Q3 Cool Time
System User Guide
Document Number: D5030863 A
Parameter Use
Type
Compound The CXP parameter is only used in
Q3 and MS/MS-type scans, where
it transmits the ions into Q3.
Use the preset value and optimize
for the compound.
Compound This is the amount of energy that
the precursor ions receive as they
are accelerated into Q3, where
they collide with gas molecules and
fragment.
Use the preset value.
Compound The Q3 Entry Barrier parameter is
used to transfer the ions from Q2
into the LIT.
Use the preset value.
Compound The Q3 Empty Time parameter
controls the amount of time that
singly-charged ions are removed
from the LIT.
Use the preset value.
Compound The MS/MS/MS Fragmentation
Time parameter controls the
amount of time that the excitation
energy is applied. It is used in
combination with the excitation
energy to fragment the isolated
second precursor ion.
Use the preset value.
Compound The MCS Barrier parameter
controls the voltage used when
eliminating the singly-charged ions
from the LIT.
Use the preset value.
Compound The Q3 Cool Time parameter
controls the amount of time that the
precursor ions are allowed to cool
prior to collection of their product
ions.
Use the preset value.
Basic Acquisition Methods
Scan Type
Q3, MRM,
MS2, Prec,
and NL
TDF
EMS, EMC,
EPI, ER, and
MS/MS/MS
EMC
MS/MS/MS
EMC
TDF
4500 Series of Instruments
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