School of Nano Science, Institute for Research in Fundamental Sciences (IPM), Tehran 19395-5531, Iran.
Department of Physics, Shahid Beheshti University, Evin, Tehran, Iran.
Phys Chem Chem Phys. 2023 Feb 15;25(7):5718-5730. doi: 10.1039/d2cp05499j.
The proton between the two oxygen atoms of the malonaldehyde molecule experiences an effective double-well potential in which the proton's wavefunction is delocalized between the two wells. Herein we employ a state-of-the-art multi-component quantum theory of atoms in molecules partitioning scheme to obtain the molecular structure, atoms in molecules and bonding network, from the superposed wavefunctions of malonaldehyde. In contrast to the familiar clamped-proton portrayal of malonaldehyde, in which the proton forms a hydrogen basin, for the superposed states the hydrogen basin disappears and two novel hybrid oxygen-hydrogen basins appear instead, with an even distribution of the proton population between the two basins. The interaction between the hybrid basins is stabilizing thanks to an unprecedented mechanism. This involves the stabilizing classical Coulomb interaction of the one-proton density in one of the basins with one-electron density in the other basin. This stabilizing mechanism yields a bond foreign to the known bonding modes in chemistry.
丙二醛分子中两个氧原子之间的质子经历了一个有效的双势阱，其中质子的波函数在两个势阱之间离域。在这里，我们采用了一种最先进的多组分量子原子在分子中的分区理论，从丙二醛的叠加波函数中获得分子结构、原子在分子中和键网络。与熟悉的丙二醛的固定质子描述形成对比，在固定质子描述中，质子形成一个氢盆，对于叠加态，氢盆消失，取而代之的是两个新的混合氧-氢盆，质子在两个盆之间均匀分布。由于一种前所未有的机制，混合盆之间的相互作用是稳定的。这涉及到一个质子密度在一个盆地中的经典库仑相互作用与另一个盆地中一个电子密度的稳定。这种稳定机制产生了一种与化学中已知键合模式不同的键。
