Thanks to all. I have reached the end of this clever but ridiculously complicated puzzle. The grid consisted of elements. Thank goodness the setter didn’t include two-letter elements!
All done bar the infuriating unchecked letter in 1 across. I have one answer that could work but render the clue very weak, and another possibility which I can't parse. Please could some kind soul put me out of my misery?
Topaz...6A is an anagram of CONS (tricks)+ON+U+SENTE (senate missing an a) + A for Academician. Maybe you forgot to remove the letter a before solving this one ?