Study of substituted aryldiazonium salts and their crown ethers complexes by XPS

The complexes of fourteen substituted aryldiazonium salts RCHN+BF（R=H,p-CH,p-NO,p-I,p-Cl,p-F,m-Br,m-Cl,m-CH,o-CH,o-OCH,o-NO,o-Br,o-Cl）withcrown ethers 18-c-6（1）and dibenzo-24-c-8（2）have been studied by XPS.The results show that thechemical shifts of a-N1s and β-N1s of substituted aryldiazonium salts are closely related to theinduction and conjugation effects of R groups.It is interesting to note that charge transfer（β-N→O）take place upon complexation of substituted aryldiazonium salts with crown ethers.Therefore thedecrease of binding energy of crown ether oxygen may be used as a measurement of the stabilitiesof these complexes.