x (Pinyin) ɕ (IPA)

Voiceless alveolo-palatal sibilant
the voiceless alveolo-palatal fricative is a type of consonantal sound, used in some oral languages. the symbol in the international phonetic alphabet that represents this sound is ⟨ɕ⟩ (cee with the curl also found in its voiced counterpart ⟨ʑ⟩).

"Voiceless alveolo-palatal sibilant (vector)" by Lfdder - Own work. Licensed under CC BY-SA 3.0 via Wikipedia. "Alveolopalatal fricative" by Alveolopalatal_fricative.png: Ishwarderivative work: TyIzaeL - Alveolopalatal_fricative.png. Licensed under CC BY-SA 3.0 via Wikimedia Commons.
Features of the voiceless alveolo-palatal fricative: