RKS calculation with Doublet Multiplicity, strange?

[Natalie Austin]

Hello, 

I was running a calculation (calculation 1) with an odd number of 
electrons. The default multiplicity was set to doublet. This calculation 
ran without the UKS tag. 

I compared this calculation to one in which I included the UKS keyword in 
the input (calculation 2). The electronic energies of each calc1 and cal 2 
were comparable to 10E-7. 

I found it strange that CP2K would run a system with an odd number of 
electrons as RKS, is this because of the smearing?

Input:
&FORCE_EVAL
  METHOD QS
  &DFT
    BASIS_SET_FILE_NAME BASIS_MOLOPT
    POTENTIAL_FILE_NAME GTH_POTENTIALS
    &MGRID
      CUTOFF 500
      REL_CUTOFF 60
      NGRIDS 4
    &END MGRID
    &QS
       EPS_DEFAULT 1.0E-14
       MAP_CONSISTENT
    &END QS
  &SCF
     SCF_GUESS ATOMIC
     EPS_SCF 1.0E-8
     MAX_SCF 500
     ADDED_MOS  200
     CHOLESKY INVERSE
     &SMEAR  ON
         METHOD FERMI_DIRAC
         ELECTRONIC_TEMPERATURE [K] 300
     &END SMEAR
     &DIAGONALIZATION
          ALGORITHM STANDARD
     &END DIAGONALIZATION
     &MIXING
          METHOD BROYDEN_MIXING
          ALPHA   0.1
          BETA    1.5
          NBROYDEN  8
     &END MIXING
  &END SCF
    &XC
      &XC_FUNCTIONAL PBE
      &END XC_FUNCTIONAL
    &END XC
CHARGE -1
    &POISSON
      POISSON_SOLVER WAVELET
      PERIODIC NONE
    &END POISSON
# UKS .TRUE.        => this is uncommented in the UKS calculation
  &END DFT


Calculation 1:
 DFT| Spin restricted Kohn-Sham (RKS) calculation                           
 RKS
 DFT| Multiplicity                                                         
    2
 DFT| Number of spin states                                                 
   1
 DFT| Charge                                                               
   -1


Calculation 2
 DFT| Spin unrestricted (spin-polarized) Kohn-Sham calculation             
  UKS
 DFT| Multiplicity                                                         
    2
 DFT| Number of spin states                                                 
   2
 DFT| Charge                                                               
   -1

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