Property within estate

[TW1234]

Where there is an estate, consisting of cash (equivalents) and a 50% tenancy in common of the family home, with the residue left to spouse but a bequest exceeds the liquid cash available, can the surviving spouse inject cash into the administration process to make up the shortfall and the executors transfer the property ownership directly to her?
If so, does any stamp duty arise, where the “shortfall” amount exceeds the exempt band or is it necessary for the executors to transfer the proportion of the property into the beneficiary’s ownership and let them arrange a subsequent sale to the spouse?
Also how would the direct transfer to spouse impinge on unused IHT exemptions carried over for use ultimately by spouse? (after April 2017)

[maths]

Who is to inherit the cash bequest and who is to inherit the 50% beneficial interest in the property under the will?

[TW1234]

Bequest is to child. The property beneficial interest passes to spouse as residue.
eg estate is £k200 cash and £K200 50% of £400 property with bequest of £K325.