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the new fuels with magnecular structure - Institute for Basic Research

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THE NEW FUELS WITH MAGNECULAR STRUCTURE 169<br />

To estimate <strong>the</strong> intensity of <strong>the</strong> magnetic field which causes considerable de<strong>for</strong>mation<br />

of <strong>the</strong> ground state electron orbit of <strong>the</strong> H atom, one can <strong>for</strong>mally<br />

compare Bohr radius of <strong>the</strong> H atom in <strong>the</strong> ground state, in zero external magnetic<br />

field, a 0 = 2 /me 2 ≃ 0.53 · 10 −8 cm = 1 a.u., <strong>with</strong> <strong>the</strong> radius of orbit of a<br />

single electron moving in <strong>the</strong> external static uni<strong>for</strong>m magnetic field B. ⃗<br />

The mean radius of <strong>the</strong> orbital of a single electron moving in a static uni<strong>for</strong>m<br />

magnetic field can be calculated exactly by using Schrödinger’s equation, and it<br />

is given by<br />

R n =<br />

√<br />

n + 1/2<br />

, (A.1)<br />

γ<br />

where γ = eB/2c, B is intensity of <strong>the</strong> magnetic field pointed along <strong>the</strong> z axis,<br />

⃗B = (0, 0, B), ⃗r = (r, ϕ, z) in cylindrical coordinates, and n = 0, 1, . . . is <strong>the</strong><br />

principal quantum number. Thus, <strong>the</strong> radius of <strong>the</strong> orbit takes discrete set of<br />

values (A.1), and is referred to as Landau radius. This is in contrast to well<br />

known classical motion of electrons in an external magnetic field, <strong>with</strong> <strong>the</strong> radius<br />

of <strong>the</strong> orbit being of a continuous set of values.<br />

The energy levels E n of a single electron moving in said external magnetic field<br />

are referred to as Landau energy levels,<br />

E n = E ⊥ n + E ‖ k z<br />

= Ω(n + 1 2 ) + 2 k 2 z<br />

2m ,<br />

(A.2)<br />

where Ω = eB/mc is so called cyclotron frequency, and k z is a projection of <strong>the</strong><br />

electron momentum ⃗ k on <strong>the</strong> direction of <strong>the</strong> magnetic field, −∞ < k z < ∞, m<br />

is mass of electron, and −e is charge of electron.<br />

Landau’s energy levels En<br />

⊥ correspond to a discrete set of round orbits of <strong>the</strong><br />

electron which are projected to <strong>the</strong> transverse plane. The energy E ‖ k z<br />

corresponds<br />

to a free motion of <strong>the</strong> electron in parallel to <strong>the</strong> magnetic field (continuous<br />

spectrum), <strong>with</strong> a conserved momentum k z along <strong>the</strong> magnetic field.<br />

In regard to <strong>the</strong> above review of Landau’s results, we recall that in <strong>the</strong> general<br />

case of a uni<strong>for</strong>m external magnetic field <strong>the</strong> coordinate and spin components of<br />

<strong>the</strong> total wave function of <strong>the</strong> electron can always be separated.<br />

The corresponding coordinate component of <strong>the</strong> total wave function of <strong>the</strong><br />

electron, obtained as an exact solution of Schrödinger equation <strong>for</strong> a single<br />

electron moving in <strong>the</strong> external magnetic field <strong>with</strong> vector-potential chosen as

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