Work function, of the elements

WF Work Function is an electron work function of the elements a quantity (eV) that determines the extent to which emission will occur. The experimental method thermoionic, field emission, photoelectric, and contact potential difference at the experimental conditions (e.g., vacuum of 10 8 Pa, clean surfaces, and identifi-cation of crystal-face distribution). 

Random and systematic errors are characteristics of the method, not the values. Random errors can be determined by repeating the experiment. Systematic errors can only be determined by comparisons of values determined by different methods. Uncertainties can be estimated from precision and accuracy plots if it is assumed that there are only random errors. The Ea of the d and f block elements, electronegativities, and work functions of the elements will be evaluated in this chapter using this procedure. 

The extrapolation of values in the Periodic Table for the main group of elements can be examined and applied to the transition elements. The evaluated values can be combined with ionization potentials to obtain Mulliken electronegativities. These may be correlated with other electronegativities and the work functions of the elements. This provides another example of the use of the Periodic Table to evaluate and predict values. 

Figure 8.10 Plots of the Mulliken, electronegativities, and work functions of the elements versus the atomic number to illustrate their consistency and differences [43, 44].

Herbert B. Michaelson. The work function of the elements and its periodicity. Journal of Applied Physics, 48(ll) 4729-4733, 1977. 

Since measurements reported in the literature often cover a considerable range. This table contains selected values for the electron work function of the elements which may be regarded as typical values for a reasonably clean surface. The method of measurement is indicated for each value. The following abbreviations appear ... 

The work functions of the elements gold, vanadium, magnesium and barium are 492, 415, 353 and 261 kJ mol", respectively. Calculate the threshold frequencies of radiation which will liberate photoelectrons from the surface of the elements. 

Electron volt, 1-1 to 11,1-23 to 26 Electron Work Function of the Elements,... 

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