根据tutorial，应该是使用自带程序reordermo。但是由于手册中的案例无需换轨道便没有给出具体案例。Usually, the active orbitals obtained in the first MCSCF calculation do not correspond to the active space that we have in mind.
When that happens, it is necessary to reorder the molecular orbital file and run the MCSCF calculation again.
COLUMBUS distribution contains an auxiliary program called reordermo.x to do this task.
This program may be accessed through the 7) Utilities option in colinp.
我计算的体系是C1对称性，74个电子，在cas(10,8)下进行计算。需要对32，33轨道进行交换。
进入程序Utilities的reordermo后提示：
Enter MOs to reorder as triples
<DRT> <initial position> <final position>
Please enter a complete permutation for every DRT
根据提示输入了 1 32 33
出现报错：Error occurred in reordermo.x errno=256, check runc.error
输出文件reordermols报错信息如下：
===== Program reordermo =====
------------------------------------------------------------------------
&input
mocoef='MOCOEFS/mocoef_mc.sp'
reordered='MOCOEFS/mocoef.new'
newmo(32,1)=33,
&end
------------------------------------------------------------------------
implicit mapping error newmo(33, 1)= 0
bummer (warning):incomplete permutation for drt # 1
mapping error:
the new mo number on the right hand side appears
several times for one DRT.
implicit mapping error:
there was no complete permutation defined, hence
collision with the implicit mapping, i.e. newmo(j,i)=j
bummer (fatal):input errors!2