Is there a good formula and preparation method available for a diazepam syrup?

diazepam 60 mg
Citric acid monohydr 125 mg
excipient Pro of with xanthan gum 45g
sorbitol 70% not crystallizable (NC) 45 g
Aqua Conservans up to 150 ml
possibly Raspberry essence 450 mg

Preparation:
Apply the diazepam in a mortar together with the citric acid; rub; place in a small beaker 50 g exc. Pro Susp. and add a small amount to the diazepam and citric acid; mix soundly to the absence of Agglomerates Gradually add excipient to the mixture until another 5 gr remains in the Beaker (method by Backroads); Mix after each addition; Weigh in the mortar 45 g sorbitol 70% NC and mix; Pour the suspension into a measuring glass and rinse the mortar repeatedly with Aqua Conservans until a volume of 150 ml is obtained.

on the basis of the optimal pH, one shelf life of 3 months after preparation is assumed.