method Items.UnmergeCells ([Cell as Variant])
Unmerges a list of cells.

Cell as Variant A long expression that indicates the handle of the cell being unmerged, or a safe array that holds a collection of handles for the cells being unmerged. Use the ItemCell property to retrieves the handle of the cell.
Use the UnmergeCells method to unmerge merged cells. Use the MergeCells method or CellMerge property to combine ( merge ) two or more cells in a single one. The UnmergeCells method unmerges all the cells that was merged. The CellMerge property unmerges only a single cell. The rest of merged cells remains combined.

The following sample shows few methods to unmerge cells: