## 3 Results and Discussion  
### Crystal Structures  
All crystallographic measurements were performed using graphite monochromated MoKa radiation at 100(2) K. The structure of complexes **1** and **3** agrees well with the previously reported X-ray data shown in Figure 2[26; 28]. All relevant crystallographic data as well as selected interatomic distances and bond angles can be taken from Tables S1-S4 (Supplementary data). Interestingly, the low temperature X-ray structure of [Ag(2-pyridone)NO\({}_{3}\)]\({}_{n}\); (**2**) complex showed some variations compared to the previously reported room temperature (293(2) K) data [27]. Hence, its structure will be described in some details in this publication. The asymmetric unit of [Ag(2-pyridone)NO\({}_{3}\)]\({}_{n}\); (**2**) contains three independent AgL(NO\({}_{3}\)) complexes (Figure 2), which differ slightly by their Ag-O(NO\({}_{2}\)) bond distances and O-Ag-O bond angles. The coordination geometry of Ag(I) have one short Ag-O bond (2.307-2.316(4) A) to the organic ligand and longer bonds (2.533(4) A, Ag3-O9, to 2.666(5) A, Ag2-O12) to the nitrate anions. On other hand, the main difference between the newly reported structure of **2** with the previously reported data by [PERSON] and coworkers is that the asymmetric unit of the latter comprised one AgL(NO\({}_{3}\)) unit in which the corresponding Ag-O distances are 2.315(6) and 2.588(8) to 2.715(10) A, respectively.  
The crystal structure of [Ag(2-pyridone)NO\({}_{3}\)]\({}_{n}\) is built up by a strongly folded 2D-infinite network of silver cations and nitrate anions parallel to the _ab_ plane of the unit cell (Figure S3; Supplementary data) where the coordination geometry of the Ag(I) could be simply described as distorted tetrahedral as shown in Figure S4 (Supplementary data). These are interconnected by the 2-pyridone ligands by formation of two strong hydrogen bonds with the \(R\)2,_(_8_) pattern between two neighboring ligands (N-H...O distances: N-H: 0.879 A, H...O: 1.922 A for O3-H1, 1.924 A for O2-H3B and 1.932 A for O1-H2B) as shown in Figure 3. This is a common motif for lactam dimers [54]. The structure is best understood  
Figure 2: The X-ray structure of complexes **1**–**3**.  
as a 3D net with the _ins_-topology, illustrated in Figure 4. The topology is binodal, containing one type of 3-connected node and one type of 4-connected node. This topology is rather rare, but has also been found in the coordination polymer [Ag\({}_{3}\)(hexamethylenetetramine)\({}_{2}\)][ClO\({}_{4}\)]\({}_{3}\)\(2\)H\({}_{2}\)O [55].  
Indeed, the ADDSM option of the software package PLATON suggests a transformation to another unit cell with only 1/3 of the initial volume and thus only one formula unit per asymmetric unit [27]. However, even if this may correspond to the network topology, this is not the correct description of the symmetry of the studied complex. A refinement with the smaller unit cell led to implausible atomic displacement parameters, high standard deviations of the positional parameters, and much higher R-values.  
Figure 4: Node assignment (top) and resulting ins-net in [Ag(2-pyridone)NO\({}_{3}\)]\({}_{n}\); **2** (center) and the ideal ins-net (bottom).  
Figure 3: Projection of the structure of [Ag(2-pyridone)NO\({}_{3}\)]\({}_{n}\) along the crystallographic \(a\)-axis.