Talk:Madelung constant

sech
what is sech in the converging formula for the Madelung constant of NaCl ? — Preceding unsigned comment added by 37.138.169.178 (talk) 13:57, 25 October 2019 (UTC)


 * Sech(x) is the hyperbolic secant of x. 2804:14D:4683:10CD:9184:E581:DE56:E4E (talk) 14:43, 27 November 2023 (UTC)

any example how to use it?