Schrödinger's equation developed the idea from a flat two-dimensional Bohr atom to the three-dimensional wave function model.
The error in the historical introductory approach to atomic structure is the "planetary" model for atomic orbitals, ala the Bohr atom.
This model was eventually superseded by the Bohr atom, incorporating some early results from quantum mechanics.
This fundamental constant first appeared in the Bohr atom for Bohr radius:
In the general case, resonance energy could be due to the "rest mass" of electron, energy gap for Bohr atom, etc.
Contrary to the spherical Bohr atom, the FA has gyperbolic dependence on the number of energy level (n)
Although perturbation theory was used in the semi-classical theory of the Bohr atom, the calculations were monstrously complicated, and subject to somewhat ambiguous interpretation.
The Bohr atom was just a staging post on the way to the quantum world rather than the point of entry into the land itself.
The unit energy in this system is the total energy of the electron in the Bohr atom and called the Hartree energy.
Zodiacal symbols on the deep blue ceiling encircled a golden Bohr atom.