In which the 
  
    
      
        λ
      
    
    {\displaystyle \lambda }
   is the reorganisation energy. Filling this result in the classically derived Arrhenius equation

leads to

With A being the pre-exponential factor which is usually experimentally determined, although a semi classical derivation provides more information as will be explained below. This classically derived result qualitatively reproduced observations of a maximum electron transfer rate under the conditions 
  
    
      
        Δ
        
          G
          
            †
          
        
        =
        λ
      
    
    {\displaystyle \Delta G^{\dagger }=\lambda }
  . For a more extensive mathematical treatment one could read the paper by Newton.
A rickettsiosis is a disease caused by intracellular bacteria. Cause
Rickettsioses can be divided into a spotted fever group (SPG) and typhus group (TG).In the past, rickettsioses were considered to be caused by species of Rickettsia. However, scrub typhus is still considered a rickettsiosis, even though the causative organism has been reclassified from Rickettsia tsutsugamushi to Orientia tsutsugamushi.Examples of rickettsioses include typhus, both endemic and epidemic, Rocky Mountain spotted fever, and Rickettsialpox. Organisms involved include Rickettsia parkeri.Many new causative organisms have been identified in the last few decades. Most are in the genus Rickettsia, but scrub typhus is in the genus Orientia. Diagnosis
No rapid laboratory tests are available to diagnose rickettsial diseases early in the course of illness, and serologic assays usually take 10–12 days to become positive. Research is indicating that swabs of eschars may be used for molecular detection of rickettsial infections. Treatment
Doxycycline has been used in the treatment of rickettsial infection. References
External links
 Media related to Rickettsioses at Wikimedia Commons