with dendrimers [10, 11], as well as with their related core–shell (tecto)dendrimers
[48, 165]. In the case of atomic elements (i.e., far left column) outer electron shell
saturation is fulfilled by autoreaction to produce an elemental dimer. In the middle
column, the penultimate dendrimer species to the saturated ideal dendrimer structure presents an isolated functional group (i.e., amine or ester) in the outer monomer
shell that may react with a co-reactive functional group (i.e., amine or ester) on the
surface of a neighboring dendrimer to give dimer formation [10, 11]. Therefore,
these two nanoscale dendrimer scaffoldings that combined to form dimer appear to
be heuristically mimicking elemental atoms and, as such, are individually referred
to as “soft superatoms” [141]. As illustrated in Fig. 22, core–shell tecto(dendimers)
were also observed to follow an analogous autoreactivity pattern associated with
unsaturated outer dendrimer shells [48, 165].
Monomer Aufbau
Unfilled Monomer Shells
Monomer Shells
(Generations)
Unfilled Shell
(Core)
N c =3
N c =3: N b =2 N
c =3: N b =2
N c =3: N b =2 N c =3: N b =2 N c =3: N b =2 N c =3: N b =2
[0] 3 :[1] 1
[0] 3 ; [1] 6 ; [2] 11
N c =3: N b =2
[0] 3 : [1] 6 : [2] 1
N c =3: N b =2
[0] 3 : [1] 6 : [2] 3
N c =3: N b =2
[0] 3 : [1] 6 : [2] 5
N c =3: N b =2
[0] 3 : [1] 6 : [2] 7
N c =3: N b =2
[0] 3 : [1] 6 : [2] 9
N c =3: N b =2
[0] 3 : [1] 6 : [2] 1
N c =3: N b =2
[0] 3 : [1] 6 : [2] 12
4
0
1 (x)
2
13
15
17
19
21
G2
G2
G2
G1
G0
G3
G4
11
20
5
6
7
1
2
3
8
9
[0] 3 :[1] 2
[0] 3 :[1] 3
[0] 3 :[1] 4
[0] 3 :[1] 5
[0] 3 :[1] 6
N c =3
[0]
1
N 0 =3
N c =3
[0]
2
[0]
3
Filled Monomer Shells
Dendrimers
saturated
shells
Fig. 21 Heuristic dendrimer-based periodic table based on monomer shell filling. Monomer
aufbau stages (i.e., G ¼ 0–4) mimic respective electron shell-filling stages in atoms. Autoreactive
dendrimer species reside penultimate to the outer-shell-saturated stick configurations mimicking
noble gas elements. These unfilled shell species are autoreactive, producing G ¼ 2 dimers,
wherein dendrimer species possessing 20 monomer units represent a “superatom” analog of
elemental chlorine. The 21-monomer, shell-saturated analog is a G ¼ 2 dendrimer mimicking
argon. Molecular simulations of ideal, outer-shell-saturated dendrimer generations (i.e., G ¼ 0–4)
( far right column) are shown next to the core–shell (i.e. shell-saturated) stick configurations
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D.A. Tomalia
[48, 165]. In the case of atomic elements (i.e., far left column) outer electron shell
saturation is fulfilled by autoreaction to produce an elemental dimer. In the middle
column, the penultimate dendrimer species to the saturated ideal dendrimer structure presents an isolated functional group (i.e., amine or ester) in the outer monomer
shell that may react with a co-reactive functional group (i.e., amine or ester) on the
surface of a neighboring dendrimer to give dimer formation [10, 11]. Therefore,
these two nanoscale dendrimer scaffoldings that combined to form dimer appear to
be heuristically mimicking elemental atoms and, as such, are individually referred
to as “soft superatoms” [141]. As illustrated in Fig. 22, core–shell tecto(dendimers)
were also observed to follow an analogous autoreactivity pattern associated with
unsaturated outer dendrimer shells [48, 165].
Monomer Aufbau
Unfilled Monomer Shells
Monomer Shells
(Generations)
Unfilled Shell
(Core)
N c =3
N c =3: N b =2 N
c =3: N b =2
N c =3: N b =2 N c =3: N b =2 N c =3: N b =2 N c =3: N b =2
[0] 3 :[1] 1
[0] 3 ; [1] 6 ; [2] 11
N c =3: N b =2
[0] 3 : [1] 6 : [2] 1
N c =3: N b =2
[0] 3 : [1] 6 : [2] 3
N c =3: N b =2
[0] 3 : [1] 6 : [2] 5
N c =3: N b =2
[0] 3 : [1] 6 : [2] 7
N c =3: N b =2
[0] 3 : [1] 6 : [2] 9
N c =3: N b =2
[0] 3 : [1] 6 : [2] 1
N c =3: N b =2
[0] 3 : [1] 6 : [2] 12
4
0
1 (x)
2
13
15
17
19
21
G2
G2
G2
G1
G0
G3
G4
11
20
5
6
7
1
2
3
8
9
[0] 3 :[1] 2
[0] 3 :[1] 3
[0] 3 :[1] 4
[0] 3 :[1] 5
[0] 3 :[1] 6
N c =3
[0]
1
N 0 =3
N c =3
[0]
2
[0]
3
Filled Monomer Shells
Dendrimers
saturated
shells
Fig. 21 Heuristic dendrimer-based periodic table based on monomer shell filling. Monomer
aufbau stages (i.e., G ¼ 0–4) mimic respective electron shell-filling stages in atoms. Autoreactive
dendrimer species reside penultimate to the outer-shell-saturated stick configurations mimicking
noble gas elements. These unfilled shell species are autoreactive, producing G ¼ 2 dimers,
wherein dendrimer species possessing 20 monomer units represent a “superatom” analog of
elemental chlorine. The 21-monomer, shell-saturated analog is a G ¼ 2 dendrimer mimicking
argon. Molecular simulations of ideal, outer-shell-saturated dendrimer generations (i.e., G ¼ 0–4)
( far right column) are shown next to the core–shell (i.e. shell-saturated) stick configurations
360
D.A. Tomalia