Highly accurate, inexpensive procedures for computing theoretical chronoamperometric currents at single straight electrode edges and at single microband electrodes

作者：Bieniasz L K^*

来源：Journal of Electroanalytical Chemistry, 2016, 760: 71-79.

DOI：10.1016/j.jelechem.2015.11.040

• Edge effects
• Microband electrode
• Chronoamperometry
• Limiting current
• Minimax approximation
• Mathieu functions

Theoretical considerations of potential step chronoamperometry for electrochemical systems involving straight electrode edges lead to a number of analytical or semi-analytical expressions, or special functions, describing current-time dependences. Unfortunately the functions are hard to evaluate accurately on a computer, due to numerical difficulties or high computational costs. In this work computationally inexpensive procedures have been developed, for two special functions describing chronoamperometry at a single straight edge and for one special function expressing chronoamperometric current at a single microband electrode (two straight edges). The concept of the minimax approximation has been employed. The procedures are highly accurate, ensuring relative errors close to, or even smaller than 10(-16), which is the machine accuracy for standard double precision variables. In addition, computing a single function value requires less than a microsecond of the processor time on currently available personal computers. The procedures can be useful for the purposes of experimental data analysis, and for the testing/validation of diverse mathematical and numerical modelling techniques designed for electroanalyticat chemistry.

• 出版日期2016-1-1