Lqd crystl (LC) s stt f mttr whs prprts r btwn ths f cnvntnl lqds nd ths f sld crystls. Fr xmpl, lqd crystl cn flw lk lqd, bt ts mlcls my b rntd n cmmn drctn s n sld. Thr r mny typs f LC phss, whch cn b dstngshd by thr ptcl prprts (sch s txtrs). Th cntrstng txtrs rs d t mlcls wthn n r f mtrl ("dmn") bng rntd n th sm drctn bt dffrnt rs hvng dffrnt rnttns. n LC mtrl my nt lwys b n n LC stt f mttr (jst s wtr my b c r wtr vpr).
Lqd crystls cn b dvdd nt thr mn typs: thrmtrpc, lytrpc, nd mtlltrpc. Thrmtrpc nd lytrpc lqd crystls cnsst mstly f rgnc mlcls, lthgh fw mnrls r ls knwn. Thrmtrpc LCs xhbt phs trnstn nt th LC phs s tmprtr chngs. Lytrpc LCs xhbt phs trnstns s fnctn f bth tmprtr nd cncntrtn f mlcls n slvnt (typclly wtr). Mtlltrpc LCs r cmpsd f bth rgnc nd nrgnc mlcls; thr LC trnstn ddtnlly dpnds n th nrgnc-rgnc cmpstn rt.
xmpls f LCs xst bth n th ntrl wrld nd n tchnlgcl pplctns. Lytrpc LCs bnd n lvng systms; mny prtns nd cll mmbrns r LCs, s wll s th tbcc msc vrs. LCs n th mnrl wrld ncld sltns f sp nd vrs rltd dtrgnts, nd sm clys. Wdsprd lqd-crystl dsplys (LCD) s lqd crystls.