NOVELTY - Preparing group 1a-1b-3a-6a material (A1) comprises: providing substrate; optionally, providing group 1a source containing sodium; providing group 1b source; providing group 3a source; optionally, providing group 6a sulfur source; providing group 6a selenium source containing a selenium ink with selenium compound (I) and a liquid carrier; forming group 1a-1b-3a-6a precursor material on substrate by optionally using e.g. group 1a source to apply sodium to the substrate; and treating the precursor material to form (A1).    USE - The method is useful for preparing: group 1a-1b-3a-6a material (claimed) that is used in semiconductor material (thin layer transistors, solar cells, electrophotography components, rectifiers, photographic exposure meters and photocopying media) and chalcogenide containing phase change memory devices; and copper indium gallium (di)selenide (CIGS) material that is used in photovoltaic devices.    ADVANTAGE - The method: utilizes selenium that is hydrazine and hydrazinium free, and stable (claimed); and provides uniform or graded semiconductor films comprising selenium to facilitate improved separation of the photogenerated charge carriers and reduced recombination at the back contact and tailor the CIGS material composition to achieve desired grain structure and highest efficiency photovoltaic device characteristics.    DETAILED DESCRIPTION - Preparing a group 1a-1b-3a-6a material of formula (NalXmY1nSpSeq) (A1) comprises: providing a substrate; optionally, providing a group 1a source containing sodium; providing a group 1b source; providing a group 3a source; optionally, providing a group 6a sulfur source; providing a group 6a selenium source, where the selenium source includes a selenium ink with selenium compound of formula (RZ-Sex-Z1R1) (I) and a liquid carrier that is a nitrogen containing solvent, and the selenium ink comprises greater than 1 wt.% of selenium; forming at least one group 1a-1b-3a-6a precursor material on substrate by optionally using the group 1a source to apply sodium to the substrate, group 1b source to apply a group 1b material to the substrate, group 3a source to apply a group 3a material to the substrate, optionally sulfur source to apply a sulfur material to the substrate and selenium source to apply a selenium material to the substrate; and treating the precursor material to form (A1).    Z, Z1 = S, Se or Te;    x = 2-20;    R = R1 or H;    R1 = 1-20C alkyl, 6-20C aryl, 1-20C alkyl hydroxy, aryl ether or alkyl ether;    X = at least one group 1b element comprising Cu or Ag;    Y1 = at least one group 3a element comprising Al, Ga or In;    l = 0-0.75;    m = 0.25-1.5;    n = 1;    p, q = 0-2.5; and    p+q = 1.8-2.5.