I use the relativistic Compton equations to calculate the momentum response of a ‘target’ electron to vacuum photon collisions redirected from a ‘source’ electron. The equations give the ratio of the momentum of the ‘target’ electron after the collision divided by the momentum of the incoming photon over the range of all angles of the ‘target’ electron’s deflection. By summing evenly (over the maximum cross-section) over all angles we obtain the ratio of 1/2.1412 when using photon frequencies of 2 and 4 times the mass equivalence of an electron in the ratio of 5.6269 to 1. 4 times the mass equivalence may be 2 x (2 times electron mass equivalence photons acting simultaneously) or a double photon composite.The fraction 1/8 is a probability based on spherical geometry — the ratio of the maximum cross-sectional area of a sphere to its surface area (¼) and a further probability of (½) due to the even chance of the electromagnetic properties of a photon matching those of an electron. This gives a total probability of (¼) x (½) = 1/8. There are 2 such 1/8 probability collisions — one in which a photon is deflected by a ‘source’ electron towards a ‘target’ electron and a second 1/8 probability collision at the ‘target’ electron. The Fine Structure Constant is therefore divided into 3 parts.1/8 x 1/8 x 1/2.1412 = 1/137.0360 based on probability, spherical geometry and the use of the Compton scattering equations. 1/2.1412 {0.4670} is calculated using the Compton scattering equations. 1/2.1412 x 1/8 (probability) gives 1/17.1295 {0.05838} Coulomb’s Law. 1/17.1295 x 1/8 (probability) gives 1/137.0360 {0.007297} the Fine Structure Constant. A ‘free’ electron may be pictured/averaged as a speed of light particle contained in an approximately circular orbit with fixed angular momentum by collisions with vacuum momenta.