TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Processes: A chloro or alkyl ester of a squaric acid derivative of formula (24) or croconic acid derivative of formula (25) is formed using aromatic compound or olefinic compound by reacting with cyclobutene derivative of formula (III) or cyclopentene derivative of formula (IV) respectively. The obtained condensation product is reacted with aromatic compound (a1) of formula: H2C=Ar2, or olefinic compound of formula: (H3C-Ar2).Hal-, respectively to form chromophore such as squarylium dye (5) or croconium dye (6). A halo chromophore of formula: M'-Hal, and a metalated conjugated system of formula: M-S', are coupled in presence of palladium or copper to form coupled component of formula: M'-S'. A carboxyaldehyde group is introduced into the conjugated system in presence of phosphorus chloride oxide (POCl3)/dimethylformamide or butyl lithium/dimethylformamide to form component (a3) of formula: M'-S'-C(=O)-H. The resulting product is reacted with a reagent and condensed to form dye of formula: M'-S'-CH=C(-A)-G, or the resulting product is reacted with a reagent of formula: A-CH2-Gp to form halo chromophore and a metalated conjugated system (a4) of formula: M-S'-CH=C(-A)-Gp, or metalated chromophore of formula: M'-M, and a halo conjugated system of formula: Hal-S'-CH=C(-A)-Gp. The resulting component is reacted in presence of palladium or copper to form dye of formula: M'-S'-CH=C(-A)-Gp. The anchoring group of formula: asterisk=C(-A)-Gp, is hydrolyzed in presence of acid or base to form anchoring group (1).E=Cl or alkoxy, preferably ethoxy, propoxy, iso-propoxy or butoxy;M=Sn(alkyl)3, B(OR')2, MgHal, ZnR-2;R'=alkyl, preferably 1-12C alkyl;andGp=-COOR, -SO3R, -PO3R2, -BO2R2, -SR, -OR, -NR2.Preferred Compound: The dye is of formulae (2,4, 16-18, or 20), such as ruthenium complex of formulae (19 or 21).M'=chromophore of formulae (5 or 6, 13 or 14, a15-f15), ruthenium bis(bipyridyl) complex;S'=conjugated system of formulae (a3-i3), preferably thiophene;n1,n2=0-12, preferably n1 is 0-3 and n2 is 1-7;R3=H, -(CH2)nCH3, -(CH2)n-COOR, -(CH2)n-OR, -(CH2)n-SR, -(CH2)n-NR2, -((CH2)p-O)n-CH3;p=1-4;R1,Z=halogen such as Cl, Br, F or I, NO2, NH2, CN, SO3H, OH, H, -(CH2)nCH3, -(CH2)n-COOR, -(CH2)n-OR, -(CH2)n-SR, -(CH2)n-NR2, -((CH2)p-O)n-CH3;X1,Y1=-CH2, oxygen, sulfur or NR;X,Y'=oxygen, sulfur, NR or C(CN)2, X is preferably isothiocyanato;Ar1,Ar2=aromatic group or heteroaromatic group of formulae (1a-44a), preferably (a8-g8);andr=0-4, preferably 0-2.Preferred Components: The chromophore is a squarylium dye derivative or a croconium dye derivative, or a semi-squarylium dye derivative or a semi-croconium dye derivative. The semi-squarylium dye derivative and said semi-croconium dye derivative, and the squarylium dye derivative and croconium dye derivative have aromatic ring systems (Ar1 and Ar2) attached to a squaric acid or croconic acid derivative. The chromophore comprises an organic chromophore and metal complex of formula: LL'M-(X')q or L"M1.M=ruthenium, osmium or iridium, preferably ruthenium;X'=Cl, Br, I, CN, -NCS, preferably -NCS;q=0-4, preferably 2 or 3;L,L'=organic heterocyclic ligands containing nitrogen atoms which are linked by N-atoms to respective metal M, and L and/or L'linked to anchoring group or conjugated system by any of C-atoms within ligands, preferably mono-or-polycyclic condensed ring of formulae (a10-f10), or rings covalently bonded to each other, L is 4,4'-dinonyl-2,2'-bipyridine;M1=palladium, platinum or nickel, preferably palladium;andL"=organic heterocyclic ligand of formulae (a12-d12) containing nitrogen atoms which are linked by N-atoms to respective metal M1 and to anchoring group or conjugated system by C-atoms within ligand.Preferred Properties: The chromophore in the dye is a molecule that is able to absorb in the wavelength of visible and/or IR light, preferably 300-1200 nm. The dye is chemisorbed to a photoactive semiconductor layer. The dye is red-dye and/or black-dye. The dye is present in solution or film. Preferred Definitions:    G=-COOH;and    A=-CN.    EXAMPLE - A bromo chromophore of formula (IIIa) (1 mol%) and tributyl stannyl-thiophene (1 eq) were reacted in presence of palladium catalyst (Pd(PPh3)4) and cesium fluoride at 120 degrees C for 12 hours to form squarylium dye of formula (IVa). The obtained compound was dissolved in dimethyl fluoride, phosphorus chloride oxide was added and stirred at 70 degrees C for 4 hours. The mixture was neutralized with sodium hydroxide, and extracted with dichloromethane under reduced pressure. The resulting component was reacted with cyanoacetic acid to obtain bluish green powder of dye of formula (Va).