# Has anyone actually prepared Zn(HCO3)2 absent the presence of pressurized aqueous CO2?

Under normal conditions, I am not certain, as per Atomistry on $$\ce{ZnCO3}$$, the following quote:

The hemihydrate, $$\ce{2ZnCO3.H2O}$$, was obtained by precipitating the solution of a zinc salt with ammonium bicarbonate and digesting the gelatinous precipitate in excess of the precipitant till it became crystalline.

where I would have expected zinc bicarbonate, and further:

The basic zinc carbonate, $$\ce{5ZnO.2CO2.4H2O}$$, can be prepared by the direct hydrolysis of the normal carbonate, or by boiling a solution of zinc, zinc hydroxide, or zinc carbonate in an excess of aqueous carbonic acid.

And finally, a reference to a presumably formed zinc bicarbonate, and at times, citing the employment of pressure:

Basic zinc carbonates can be converted into the normal carbonate by contact with water charged with carbon dioxide under pressure. The normal carbonate is itself somewhat soluble in water containing carbon dioxide - presumably forming the bicarbonate.

The last quote is unclear, in my opinion, as to whether under normal experimental conditions, should one expect the creation of a stable $$\ce{Zn(HCO3)2}$$?