Every character on Jiǎoluò Shūwū read as zhong in any tone — 2 readings total across the four tones. Pick the tone you mean.
If you have the sound zhong but not the character, here are the 2 characters read this way: 中 (zhōng, middle, China, to hit the mark), 重 (zhòng, heavy, important; again, to repeat). They split across 2 tones, so the tone is what separates them.