[molpro-user] correlation energy contributions

[Jacky LIEVIN]

Dear users,

Could somebody help me to interpret the warning I got about 
correlation energy contributions of states 3 and 4 in the example 
below?

  Reference coefficients greater than 0.0500000
  ---------------------------------------------
  22++0202++          -0.3582557   0.0005722  -0.2656376   0.8597017
  22+0+202++           0.8315206  -0.0011162   0.2763124   0.4338901
  220++202++           0.2583865   0.6923525  -0.6328588  -0.0875731
  22+++2+200          -0.2576458   0.6899833   0.6357727   0.0878783

  Energy contributions of internal configurations for state 3
  -----------------------------------------------------------

    NUMBER        NORM          ECORR1        OCCUPATION

   1638       0.00591006     1.29481607       2210120211

  Energy contributions of internal configurations for state 4
  -----------------------------------------------------------

    NUMBER        NORM          ECORR1        OCCUPATION

   1636       0.00110476     1.43059096       2211020211
   1638       0.00621729    -1.34938921       2210120211

Does it mean that the active space is not adequate?

By the way I would also like to better understand the analysis 
provided for each state, like for instance for state 3, in the same 
calculation:

  RESULTS FOR STATE 3.2
  =====================

  Coefficient of reference function:   C(0) =-0.97553455

  Energy contributions of configuration classes

  Class           Norm          ECORR1        ECORR2
  ---------------------------------------------------
  Internals    0.00760377    0.00000000   -0.00100137
  Singles      0.02299148   -0.06854146   -0.06825837
  Pairs        0.02019175   -0.06984040   -0.06912211
  Total        1.05078701   -0.13838185   -0.13838185
  ---------------------------------------------------

How are the contributions calculated? What is the meaning of ECORR1 and ECORR2?

Many thanks in advance

Jacky
-- 
----------------------------------------------------
         Jacky LIEVIN
         Universite Libre de Bruxelles
         Laboratoire de Chimie Quantique et Photophysique:
	atomes, molécules et atmosphères
         Cpi 160/09
         50 Av. F.D. Roosevelt
         B-1050 Bruxelles
         Belgium
         Tel: 32-2-650 4089
         Fax: 32-2-650 4232
----------------------------------------------------