The Bohr model is discussed in more detail elsewhere in FLAP. Niels Bohr (1885–1962) FLAP P11.3 Schrödinger’s model of the hydrogen atom COPYRIGHT © 1998 THE OPEN UNIVERSITY S570 V1.1 You will often find h/2π written as ˙. FLAP P11.3 Schrödinger’s model of the hydrogen atom COPYRIGHT © 1998 THE OPEN UNIVERSITY S570 V1.1 Louis de Broglie (1892–1987). FLAP P11.3 Schrödinger’s model of the hydrogen atom COPYRIGHT © 1998 THE OPEN UNIVERSITY S570 V1.1 The wave equation for classical waves is introduced elsewhere in FLAP, as is the Schrödinger equation for de Broglie waves. FLAP P11.3 Schrödinger’s model of the hydrogen atom COPYRIGHT © 1998 THE OPEN UNIVERSITY S570 V1.1 Quantum mechanical operators and eigenvalue equations are discussed more fully elsewhere in FLAP. See the Glossary for details. FLAP P11.3 Schrödinger’s model of the hydrogen atom COPYRIGHT © 1998 THE OPEN UNIVERSITY S570 V1.1 Operators are distinguished by the use of Roman (upright) characters with the carat symbol ^ (or hat) written above the quantity. FLAP P11.3 Schrödinger’s model of the hydrogen atom COPYRIGHT © 1998 THE OPEN UNIVERSITY S570 V1.1 Partial differentiation is introduced elsewhere in FLAP. When evaluating a partial derivative such as ∂0 /∂x the basic rule is to treat all variables other than x as though they are constants. FLAP P11.3 Schrödinger’s model of the hydrogen atom COPYRIGHT © 1998 THE OPEN UNIVERSITY S570 V1.1 We will from now on use E instead of E tot; it is to be understood that it is always the total energy that we are interested in. FLAP P11.3 Schrödinger’s model of the hydrogen atom COPYRIGHT © 1998 THE OPEN UNIVERSITY S570 V1.1 Strictly speaking we are here describing the orbital magnetic quantum number, which we designated m0l to distinguish it from the spin magnetic quantum number m0s associated with the intrinsic magnetism of the electron itself. In this module we are not concerned with electron spin and so there is no ambiguity in simply using m here, as in Yl1 m0(θ, φ ). FLAP P11.3 Schrödinger’s model of the hydrogen atom COPYRIGHT © 1998 THE OPEN UNIVERSITY S570 V1.1 There is nothing special about the z-axis itself; it is just that the angular coordinate system chosen singles out the z-axis as the one from which the angle θ is measured. The point is that the magnitude of the angular momentum and its component in one direction can be known simultaneously. We decide to call this direction the z-direction. FLAP P11.3 Schrödinger’s model of the hydrogen atom COPYRIGHT © 1998 THE OPEN UNIVERSITY S570 V1.1 Remember: if z = eiα with α real, then |1z1|2 = zz* = eiα1e−iα = 1. FLAP P11.3 Schrödinger’s model of the hydrogen atom COPYRIGHT © 1998 THE OPEN UNIVERSITY S570 V1.1 It should be noted that there are an infinite number of possible bound states. FLAP P11.3 Schrödinger’s model of the hydrogen atom COPYRIGHT © 1998 THE OPEN UNIVERSITY S570 V1.1 Pieter Zeeman (1865–1943). FLAP P11.3 Schrödinger’s model of the hydrogen atom COPYRIGHT © 1998 THE OPEN UNIVERSITY S570 V1.1 The best way to formulate the correspondence principle has been a matter of debate for many decades. Our formulation is not meant to be definitive. FLAP P11.3 Schrödinger’s model of the hydrogen atom COPYRIGHT © 1998 THE OPEN UNIVERSITY S570 V1.1 ✧ Remembering that a0 = 0.53 × 10−101m, E1 = −13.61eV, and calculating that v 1 = 2.18 × 1061m1s−1, we find r n = 10 12 × 0.53 × 10 −101m = 531m (a very large hydrogen atom!) v n = 2.181m1s−1 ∆r/r = 2 × 10 −6, or ∆r ≈ 10−41m ∆E ≈ 2.7 × 10−171eV ∆v ≈ −2 × 10−61m1s−1 so that when the change in orbital radius is just approaching visibility, the changes in energy and electron speed are negligibly small. FLAP P11.3 Schrödinger’s model of the hydrogen atom COPYRIGHT © 1998 THE OPEN UNIVERSITY S570 V1.1 In fact, we can treat all these quantities as varying continuously for sufficiently large n. This situation would be indistinguishable from classical predictions.4❏ FLAP P11.3 Schrödinger’s model of the hydrogen atom COPYRIGHT © 1998 THE OPEN UNIVERSITY S570 V1.1