In the past, I have successfully used UHF orbitals as an initial guess for a second SCF procedure. For example, with this input:

```
set basis cc-pvdz
set reference uhf
molecule h2cn {
0 2
N 0.0000000000 0.0000000000 -0.6661452159
C 0.0000000000 0.0000000000 0.5871908626
H 0.0000000000 -0.9366014853 1.1547227488
H 0.0000000000 0.9366014853 1.1547227488
}
psi4_io.set_specific_path(PSIF_SCF_MOS, '.')
psi4_io.set_specific_retention(PSIF_SCF_MOS, True)
energy('scf')
molecule h2cn {
0 2
N 0.0000000000 0.0000000000 -0.6661452159
C 0.0000000000 0.0000000000 0.5871908626
H 0.0000000000 -0.9366014853 1.1547227488
H 0.0000000000 0.9366014853 1.1547227488
symmetry c1
}
set scf guess read
energy('scf')
```

The second SCF job takes one iteration to converge, as I would expect it to.

```
SCF Guess: Guess MOs from previously saved Fock matrix.
==> Iterations <==
Total Energy Delta E RMS |[F,P]|
@DF-UHF iter 0: -93.44076220039035 -9.34408e+01 4.09110e-07
@DF-UHF iter 1: -93.44076220094324 -5.52888e-10 3.53635e-07
```

But when I submit the same input file with an ROHF reference:

```
set basis cc-pvdz
set reference rohf
molecule h2cn {
0 2
N 0.0000000000 0.0000000000 -0.6661452159
C 0.0000000000 0.0000000000 0.5871908626
H 0.0000000000 -0.9366014853 1.1547227488
H 0.0000000000 0.9366014853 1.1547227488
}
psi4_io.set_specific_path(PSIF_SCF_MOS, '.')
psi4_io.set_specific_retention(PSIF_SCF_MOS, True)
energy('scf')
molecule h2cn {
0 2
N 0.0000000000 0.0000000000 -0.6661452159
C 0.0000000000 0.0000000000 0.5871908626
H 0.0000000000 -0.9366014853 1.1547227488
H 0.0000000000 0.9366014853 1.1547227488
symmetry c1
}
set scf guess read
energy('scf')
```

the energy at the start of the second SCF procedure does not match the output energy of the first, and it takes fourteen steps to converge.

```
SCF Guess: Guess MOs from previously saved Fock matrix.
==> Iterations <==
Total Energy Delta E RMS |[F,P]|
@DF-ROHF iter 0: -42.02176950510786 -4.20218e+01 6.55809e-02
@DF-ROHF iter 1: -77.79769171277506 -3.57759e+01 7.05907e-02
@DF-ROHF iter 2: -78.40032309173856 -6.02631e-01 6.50899e-02 DIIS
@DF-ROHF iter 3: -92.86416319126418 -1.44638e+01 1.92976e-02 DIIS
@DF-ROHF iter 4: -93.34112108956496 -4.76958e-01 8.03414e-03 DIIS
@DF-ROHF iter 5: -93.42147297934090 -8.03519e-02 2.06201e-03 DIIS
@DF-ROHF iter 6: -93.42983321175151 -8.36023e-03 4.12600e-04 DIIS
@DF-ROHF iter 7: -93.43015790673918 -3.24695e-04 8.55039e-05 DIIS
@DF-ROHF iter 8: -93.43017186325338 -1.39565e-05 1.72777e-05 DIIS
@DF-ROHF iter 9: -93.43017246776162 -6.04508e-07 6.86456e-06 DIIS
@DF-ROHF iter 10: -93.43017254558441 -7.78228e-08 3.65034e-06 DIIS
@DF-ROHF iter 11: -93.43017256035043 -1.47660e-08 1.82749e-06 DIIS
@DF-ROHF iter 12: -93.43017256448108 -4.13065e-09 2.16025e-07 DIIS
```

I have had this problem on two separate machines with a version of psi that is up-to-date as of this morning. I am wondering if this is a bug, or if there is something else I need to do to successfully use ROHF orbitals as an initial guess? Maybe @jgonthier or @dgasmith would have some ideas about this??