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user168009
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I've just learned about the counterpoise correction method for Basis Set Superposition Error (BSSE).

My understanding is that the BSSE energy represents an overbinding effect due to the incomplete basis set, so it should be a negative correction that increases the interaction energy when subtracted.

$\text{BSSE} = (E_A^{AB} - E_A^A) + (E_B^{AB} - E_B^B)$

Where:

  • $E_A^{AB}\:$ Energy of fragment A in the dimer basis set (AB), including ghost orbitals from B.
  • $E_A^A\:$ Energy of fragment A in its own basis set.
  • $E_B^{AB}\:$ Energy of fragment B in the dimer basis set (AB), including ghost orbitals from A.
  • $E_B^B\:$ Energy of fragment B in its own basis set.

Is it possible to get positive BSSE error?

Is this physically meaningful, or does it indicate a problem with setup or methodology? What factors could lead to a positive BSSE value, and how should such a result be interpreted?

Edit: added energy term definitions as requested.

I've just learned about the counterpoise correction method for Basis Set Superposition Error (BSSE).

My understanding is that the BSSE energy represents an overbinding effect due to the incomplete basis set, so it should be a negative correction that increases the interaction energy when subtracted.

$\text{BSSE} = (E_A^{AB} - E_A^A) + (E_B^{AB} - E_B^B)$

Where:

  • $E_A^{AB}\:$ Energy of fragment A in the dimer basis set (AB), including ghost orbitals from B
  • $E_A^A\:$ Energy of fragment A in its own basis set.
  • $E_B^{AB}\:$ Energy of fragment B in the dimer basis set (AB), including ghost orbitals from A
  • $E_B^B\:$ Energy of fragment B in its own basis set.

Is it possible to get positive BSSE error?

Is this physically meaningful, or does it indicate a problem with setup or methodology? What factors could lead to a positive BSSE value, and how should such a result be interpreted?

Edit: added energy term definitions as requested.

I've just learned about the counterpoise correction method for Basis Set Superposition Error (BSSE).

My understanding is that the BSSE energy represents an overbinding effect due to the incomplete basis set, so it should be a negative correction that increases the interaction energy when subtracted.

$\text{BSSE} = (E_A^{AB} - E_A^A) + (E_B^{AB} - E_B^B)$

Where:

  • $E_A^{AB}\:$ Energy of fragment A in the dimer basis set (AB), including ghost orbitals from B.
  • $E_A^A\:$ Energy of fragment A in its own basis set.
  • $E_B^{AB}\:$ Energy of fragment B in the dimer basis set (AB), including ghost orbitals from A.
  • $E_B^B\:$ Energy of fragment B in its own basis set.

Is it possible to get positive BSSE error?

Is this physically meaningful, or does it indicate a problem with setup or methodology? What factors could lead to a positive BSSE value, and how should such a result be interpreted?

Edit: added energy term definitions as requested.

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Source Link
user168009
user168009
  • 1
  • 1

I've just learned about the counterpoise correction method for Basis Set Superposition Error (BSSE).

My understanding is that the BSSE energy represents an overbinding effect due to the incomplete basis set, so it should be a negative correction that increases the interaction energy when subtracted.

$\text{BSSE} = (E_A^{AB} - E_A^A) + (E_B^{AB} - E_B^B)$

Where:

  • $E_A^{AB}\:$ Energy of fragment A in the dimer basis set (AB), including ghost orbitals from B
  • $E_A^A\:$ Energy of fragment A in its own basis set.
  • $E_B^{AB}\:$ Energy of fragment B in the dimer basis set (AB), including ghost orbitals from A
  • $E_B^B\:$ Energy of fragment B in its own basis set.

Is it possible to get positive BSSE error?

Is this physically meaningful, or does it indicate a problem with setup or methodology? What factors could lead to a positive BSSE value, and how should such a result be interpreted?

Edit: added energy term definitions as requested.

I've just learned about the counterpoise correction method for Basis Set Superposition Error (BSSE).

My understanding is that the BSSE energy represents an overbinding effect due to the incomplete basis set, so it should be a negative correction that increases the interaction energy when subtracted.

$\text{BSSE} = (E_A^{AB} - E_A^A) + (E_B^{AB} - E_B^B)$

Is it possible to get positive BSSE error?

Is this physically meaningful, or does it indicate a problem with setup or methodology? What factors could lead to a positive BSSE value, and how should such a result be interpreted?

I've just learned about the counterpoise correction method for Basis Set Superposition Error (BSSE).

My understanding is that the BSSE energy represents an overbinding effect due to the incomplete basis set, so it should be a negative correction that increases the interaction energy when subtracted.

$\text{BSSE} = (E_A^{AB} - E_A^A) + (E_B^{AB} - E_B^B)$

Where:

  • $E_A^{AB}\:$ Energy of fragment A in the dimer basis set (AB), including ghost orbitals from B
  • $E_A^A\:$ Energy of fragment A in its own basis set.
  • $E_B^{AB}\:$ Energy of fragment B in the dimer basis set (AB), including ghost orbitals from A
  • $E_B^B\:$ Energy of fragment B in its own basis set.

Is it possible to get positive BSSE error?

Is this physically meaningful, or does it indicate a problem with setup or methodology? What factors could lead to a positive BSSE value, and how should such a result be interpreted?

Edit: added energy term definitions as requested.

Source Link
user168009
user168009
  • 1
  • 1

Is it possible to have a positive BSSE energy using the counterpoise method?

I've just learned about the counterpoise correction method for Basis Set Superposition Error (BSSE).

My understanding is that the BSSE energy represents an overbinding effect due to the incomplete basis set, so it should be a negative correction that increases the interaction energy when subtracted.

$\text{BSSE} = (E_A^{AB} - E_A^A) + (E_B^{AB} - E_B^B)$

Is it possible to get positive BSSE error?

Is this physically meaningful, or does it indicate a problem with setup or methodology? What factors could lead to a positive BSSE value, and how should such a result be interpreted?