*(Fig.1) Mixed antisymmetric (= between two same-spin electrons ) and symmetric (= between two opposite-spin electrons ) wavefunctions is impossible. → Quantum mechanical Pauli principle is wrong.*

In order to describe actual interactions between molecules, quantum mechanical wavefunctions have to incorporate Pauli repulsion expressed by antisymmetric wavefunction (= between two electrons with the same spin ) and molecular bond attraction expressed by symmetric wavefunctions.

↑ But this mixed antisymmetric and symmetric wavefunctions, which should explain Pauli repulsion and molecular bond attraction at the same time, are intrinsically **impossible** to make, so quantum mechanical wavefunctions can**not** describe actual Pauli repulsion and molecular bond attraction at all. → Quantum mechanics is **wrong**.

In the upper figure, φ_{A} wavefunction has the down-spin, and the other two φ_{B} and φ_{C} wavefunctions are supposed to have the up and up spins.

Hence, Pauli repulsion must occur between two electrons with the same up-up spin = two wavefunctions φ_{B} (= up-spin ) and φ_{C} (= up-spin ) must form Pauli repulsive antisymmetric wavefunctions flipping the sign by exchanging two electrons' variables belonging to φ_{B} and φ_{C} (= φ_{B} ↔ φ_{C} ).

Molecular attractive exchange energies must occur between two electrons with the opposite up-down spins = φ_{A} (= down-spin ) and the other two φ_{B} (= up-spin ), φ_{C} (= up-spin ) must form symmetric wavefunctions whose sign don't change under the exchange of two electrons' variables (= φ_{A} ↔ φ_{B} or φ_{A} ↔ φ_{C} ).

In the upper figure, the 1st equation is antisymmetric wavefunction which flips the sign by exchanging two electrons 2 and 3 (= corresponds to exchanging φ_{B} with up-spin and φ_{C} with up-spin ).

Exchanging any two electrons existing in two symmetric wavefunctions φ_{A} with down-spin and φ_{B} (= or φ_{C} ) with up-spin must keep the same sign of their wavefunctions.

For example, exchanging two electrons 1 ↔ 3 in the 1st wavefunction means exchanging two electrons of symmetric wavefunctions between φ_{A} with down-spin and φ_{B} (= or φ_{C} ) with up-spin, hence, this symmetric wavefunction should not change its sign by this exchange of two electrons.

But after all, this mixed antisymmetric (= between the same-spin electrons ) and symmetric (= between the opposite-spin electrons ) wavefunction is **impossible** to make due to cancellation of terms necessary to form symmetric wavefunctions, which become zero, as shown above.

In conclusion, quantum mechanics is **wrong**, because its Pauli antisymmetric wavefunctions cannot describe Pauli repulsion (= antisymmetric ) and molecular bond attraction (= symmetric wavefunction ) at the same time.

2022/5/25 updated. Feel free to link to this site.