  We analyze the escape of Brownian particles over potential barriers using the
Fokker-Planck equation in a similar way to that of Chandrasekhar (Rev. Modern
Phys., 1943), deriving a formula for the particle deposition velocity to a
surface as a function of the particle response time. For very small particle
response times, the particle deposition velocity reduces to that obtained using
a quasi-steady solution of Smoluchowski's equation and for very large particle
response times, the deposition velocity corresponds to that based on the
transition state method (E. Wigner, Trans. Faraday Soc., 1938).
