Cac lien hgp ion hay cac cap ion la nhung hgp chat co cong thuc chung
la [MRnlR,,;, (AH),„[MR„] hoac (MA,„|MRn (o da\ M-ion kim loaị A-bazo
huu CO, R-ph6i tu mang dien tich am) [157]. Thct^ Ku/nhexop 1157.162] cac
lien hgp ion la nhung hgp chat phuc duoc hinh thanh gom anion phuc (cua kim loai vai eac ion haloaenua), tirmm tac \ ai cac cation ha/o mau huu co de
tao thanh hop chk chiit dugc vao benzen, toluen va mot vai dung moi huu co
khac. Phan ung nay la ca sa ciia nhilu phuong phap trie quang. chilt-tric quang va huynh quang xac djnh nhilu kim loaị Ca cation bazo mau va phuc anion (chua kim loai va phli tu mang dien tich am) hoac cac anion axit nhu CIO4", CIO3", Re04'... dIu CO kich thuoc Ian [149].
Su tao thanh va chiet lien hgp ion voi cac bazo mau phu thuoc manh
vao trang thai ciia chat mau, vao do axit va ning do cua chk mau trona dung
dich. Khi nong do dam dac (10"^ - 10'^ M), xay ra su polime hoa chk mau
(thuang dime hoa), anh huang manh d^n kha nang phan ling cua ch^t mau cung nhu den cac dac tinh pho ciia cac dung dich maụ Ngoai ra, sir tao thanh cac lien hgp ion ciia cac chat mau bazo voi cac anion phuc kim loai cung phu thuoc manh vao thanh phan anion phuc. Chang han, d6i voi cac halogenua va gia halogenua, phuc kim loai tuang tac dac tnrng a dang cac ion mot dien tich
MRn+i , a day n - muc do oxi hoa ciia kim loai (vi dụ [TaP^]'. [TICI4]"...), tao
lien hgp ion Kp'^[MRn"] va phu thuoc manh vao trang thai cua cac ion kim loai trong dung dich (tuc la pH ). Them nua, phuc lien hgp ion kieu nay con phu thuoc vao do ben va nong do halogenua hoac xianuạ
Noi chung, cac lien hgp ion thuang co he so hap thu moi tirang doi cao, cho phep xac dinh nhiing lugng rat nho cac chat khac nhaụ Dieu na\ dac biet quan trgng khi co mot so cac cation bazo mau co the ket hgp voi cung mot anion phuc, vi du khi xac dinh cac nguyen to tao poliaxit di dạ Phuc lien hcTp
ion ciia Mo(VI) va W(V1) voi cac bazo mau huu co thuang dugc tao thanh
vai cac anion phirc la phuc cua Mo \a W \ai thioxianat. halogenua [??. 36.
40, 68, 138, 150], voi cac thuoc thu tao phuc anion nhu axit thiogl\colic co mat cation diphenylguanhidinhia [ 1 5 11. tricapr\ l\ lmeth\ lammonium f 1 38] ...
1.3. CAC PHirONG PHAP TACH VA LAM GIAU MOLYPDEN VA VONFRAM