--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/test-data/water_bondedparams.itp	Thu Jan 27 18:17:05 2022 +0000
@@ -0,0 +1,61 @@
+;
+; Horn et al. (2004). J. Chem. Phys.120, 9665-9678
+;
+
+
+[ moleculetype ]
+; molname	nrexcl
+SOL		2
+
+[ atoms ]
+; id  at type     res nr  res name  at name  cg nr  charge    mass
+  1   OW_tip4pew  1       SOL       OW       1       0        16.00000
+  2   HW_tip4pew  1       SOL       HW1      1       0.52422   1.00800
+  3   HW_tip4pew  1       SOL       HW2      1       0.52422   1.00800
+  4   MW          1       SOL       MW       1      -1.04844   0.00000
+
+#ifndef FLEXIBLE
+
+[ settles ]
+; i	funct	doh	dhh
+1	1	0.09572	0.15139
+
+#else
+[ bonds ]
+; i     j       funct   length  force.c.
+1       2       1       0.09572 502416.0 0.09572        502416.0 
+1       3       1       0.09572 502416.0 0.09572        502416.0 
+        
+[ angles ]
+; i     j       k       funct   angle   force.c.
+2       1       3       1       104.52  628.02  104.52  628.02  
+
+#endif
+
+
+[ virtual_sites3 ]
+; Vsite from                    funct   a               b
+4       1       2       3       1       0.106676721     0.106676721
+
+
+[ exclusions ]
+1	2	3	4
+2	1	3	4
+3	1	2	4
+4	1	2	3
+
+
+; The position of the virtual site is computed as follows:
+;
+;		O
+;  	      
+;	    	V
+;	  
+;	H		H
+;
+; Ewald tip4p:
+; const = distance (OV) / [ cos (angle(VOH)) 	* distance (OH) ]
+;	  0.0125 nm	/ [ cos (52.26 deg)	* 0.09572 nm	]
+;	then a = b = 0.5 * const = 0.106676721
+;
+; Vsite pos x4 = x1 + a*(x2-x1) + b*(x3-x1)