The present invention relates to a series of platinum acetylide nonlinear optical chromophores which are liquid at room temperature. The viscosity of these liquid chromophores is low enough that they are easily processable into optical cells and can be used for nonlinear optical applications. The compounds remain liquids below room temperature, converting to a glass in the range of from about -80.degree. C. to -100.degree. C. Neat liquids have a high chromophore concentration (.about.1 Mole/liter) making possible the development of optical devices requiring materials with a high chromophore concentration.