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the new fuels with magnecular structure - Institute for Basic Research

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THE NEW FUELS WITH MAGNECULAR STRUCTURE 173<br />

atom under <strong>the</strong> conditions here considered. For o<strong>the</strong>r atoms <strong>the</strong> critical value of<br />

<strong>the</strong> magnetic field may be evidently different.<br />

After outlining <strong>the</strong> quantum dynamics of a single electron in an external magnetic<br />

field, Aringazin [8] turns to <strong>the</strong> consideration of <strong>the</strong> H atom under an<br />

external static uni<strong>for</strong>m magnetic field.<br />

In <strong>the</strong> cylindrical coordinate system (r, ϕ, z), in which <strong>the</strong> external magnetic<br />

field is B ⃗ = (0, 0, B), i.e., <strong>the</strong> magnetic field is directed along <strong>the</strong> z-axis, Schrödinger’s<br />

equation <strong>for</strong> an electron moving around a fixed proton (Born-Oppenheimer<br />

approximation) in <strong>the</strong> presence of <strong>the</strong> external magnetic field is given by<br />

− 2<br />

2m<br />

(<br />

∂ 2 r + 1 r ∂ r + 1 r 2 ∂2 ϕ + ∂ 2 z +<br />

2me 2<br />

)<br />

2√ r 2 + z − 2 γ2 r 2 + 2iγ∂ ϕ ψ = Eψ,<br />

(A.12)<br />

where γ = eB/2c.<br />

The main problem in <strong>the</strong> nonrelativistic study of <strong>the</strong> hydrogen atom in an<br />

external magnetic field is to solve <strong>the</strong> above Schrödinger equation and find <strong>the</strong><br />

energy spectrum. This equation is not analytically tractable so that one is led to<br />

use approximations.<br />

In <strong>the</strong> approximation of a very strong magnetic field, B ≫ B 0 = 2.4·10 9 Gauss,<br />

Coulomb interaction of <strong>the</strong> electron <strong>with</strong> <strong>the</strong> nucleus is not important, in <strong>the</strong><br />

transverse plane, in comparison to <strong>the</strong> interaction of <strong>the</strong> electron <strong>with</strong> external<br />

magnetic field. There<strong>for</strong>e, in accord to <strong>the</strong> exact solution (A.4) <strong>for</strong> a single<br />

electron, one can look <strong>for</strong> an approximate ground state solution of Eq. (A.12) in<br />

<strong>the</strong> <strong>for</strong>m of factorized transverse and longitudinal parts,<br />

ψ = e −γr2 /2 χ(z),<br />

(A.13)<br />

where χ(z) is <strong>the</strong> longitudinal wave function to be found. This is so called adiabatic<br />

approximation. In general, <strong>the</strong> adiabatic approximation corresponds to<br />

<strong>the</strong> case when <strong>the</strong> transverse motion of electron is totally determined by <strong>the</strong><br />

intense magnetic field, which makes <strong>the</strong> electron “dance” at its cyclotron frequency.<br />

Specifically, <strong>the</strong> radius of <strong>the</strong> orbit is <strong>the</strong>n much smaller than Bohr<br />

radius, R 0 ≪ a 0 . The remaining problem is thus to find longitudinal energy<br />

spectrum, in <strong>the</strong> z direction.<br />

Inserting <strong>the</strong> wave function (A.13) into <strong>the</strong> Schrödinger equation (A.12), multiplying<br />

it by ψ ∗ , and integrating over variables r and ϕ in cylindrical coordinate<br />

system, one gets <strong>the</strong> following equation characterizing <strong>the</strong> z dependence of <strong>the</strong>

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