[global]

I know that 3Ca(Po3) 2  is some form of calcium phosphate, but I could not find this exact compound.  Can someone help me identify it?

[AWK]

Such compound does not exist but CaHPO₃ or Ca₃(PO₄)₂ exist.

[global]

I should have added, this compound description is from the 1950's.  Is it possible that the way to describe chemical formulas have changed since then?  I doubt it, but I'm not a chemist.
Also, can you tell me what Ca3(PO4)2 is?

[AWK]

Maybe for a chemical formula from 1850, your assumption would be true. With the correct formula in the search engine you will find hundreds of pages about this compound.

[global]

It just comes up as calcium phosphate, or tricalcium phosphate.

[AWK]

IUPAC name is tricalcium bis(phosphate) but both your names are often used as synonyms.

[David Tan]

Ca(Po3)2 does not exist because the oxidation state of Ca in this case is +6. Calcium is a Group II element and typically loses only 2 valence electrons and carries a +2 charge. The 3rd-6th electrons are removed from an inner quantum shell and is very energetically demanding.

[AWK]

Ca(Po3)2 does not exist because the oxidation state of Ca in this case is +6.

How did you find this value?

[Borek]

For the formula as written technically he is right.

Not that it helps much, and in the context most of the information posted - although correct - is just showing off.

[David Tan]

For the formula as written technically he is right.

Not that it helps much, and in the context most of the information posted - although correct - is just showing off.

This was a reply to the first post of this thread in an attempt to explain why Ca(PO3)2 is unlikely to exist. Phosphite ion has an overall charge of -3. Since we have 2 phosphite ions, the oxidation state of Ca would be +6 in this case. Respect is reciprocal. 

[AWK]

Ca(PO₃)₂ is the empirical formula of calcium metaphosphate. It is a polymer (Ca(PO3)2)n - n from 2 up. with n=2 show cyclic form of cyclotetraphosphate.
Oxidation number for P =+5

Added:
Phosphite ion has an overall charge of -2 and structure HPO₃^2-

[global]

Thanks for all the responses.  So 3Ca(Po3) 2  does not exist, how about Ca3(PO3)2 ?

[AWK]

Impossible formula

[David Tan]

Ca(PO₃)₂ is the empirical formula of calcium metaphosphate. It is a polymer (Ca(PO3)2)n - n from 2 up. with n=2 show cyclic form of cyclotetraphosphate.
Oxidation number for P =+5

Added:
Phosphite ion has an overall charge of -2 and structure HPO₃^2-

Phosphite ion is a general term used to represent the conjugate bases of H3PO3. You are absolutely correct to state that the usual representation of phosphite ion carries a -2 charge. H3PO3 has 1 P=O, 2 P-OH and 1 P-H. However if we were to draw H3PO3 as 3 P-OH with P bearing a lone pair, then it carries a -3 charge. The latter structure adopts a trigonal pyramidal shape and is less stable than the former as the former has a strong P=O which ensures that delta G is a more negative value.

[AWK]

This tautomeric form (HO)₃P  is found only in organic acid derivatives (RO)₃P and is fully covalent.