Home › Forums › Hyperfine course › electric quadrupole interaction › from toy model to quantum › answer This topic has 0 replies, 1 voice, and was last updated 1 year, 8 months ago by yury.holubeu. Viewing 1 post (of 1 total) Author Posts April 22, 2023 at 12:12 pm #4584 yury.holubeuParticipant when the nucleus becomes smaller with respect to the electron cloud $l/d$ becomes smaller, so the quadrupole term decreases in absolute value. Then the multipole expansion converges more rapidly. Author Posts Viewing 1 post (of 1 total) You must be logged in to reply to this topic. Log In Username: Password: Keep me signed in Log In