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, Table 3 Bond lengths [Å] and angles (degrees) for GAMAPbI 4 , GAMA 2 Pb 2 I 7 , and GAMA 3 Pb 3 I 10 at 293 K with estimated standard deviations in parentheses

, )-I(1) 3 Pb(1)-I(2)-Pb(1)' 180.0(5) Pb(1)-I(2) 3.2143(6) Pb(1) -I(3)-Pb, Label Distances Label Angles Pb, p.4

, Pb(1)-I(3) 3.1673(8) GAMA 2 Pb 2 I 7

, (1)-I(1) 3.168(3) Pb(1)-I(1)-Pb(1)' 159

, 159 Pb(1)-I(5) 3 Pb(1)-I(4)-Pb(2) 166.13(14) Pb(1)-I(6) 3.1910(6) Pb(1)-I(6)-Pb(1)' 173 Pb(1)-I(8) 3, )-I(8)-Pb(1)' 164.9(5) Pb(2)-I(2) 3.205(4) Pb(2)-I(9)-Pb) Pb(2)-I(3) 3.097(7) Pb(2)-I(4) 3.206(9) Pb(2)-I(7) 3.1865(4) Pb(2)-I(9) 3

, Pb(2)-I(4)-Pb(2)' 162 Pb(1)-I(6) 3.1760(7) Pb(1)-I(5)-Pb(2) 167 Pb(1)-I(7) 3.1280(7) Pb(1)-I(6)-Pb(1)' 180, Label Distances Label Angles Pb) Pb(2)-I(1) 3.092(2) Pb(1) -I(7)-Pb(1)' 167.50(19) Pb(2)-I(2) 3, p.1663

, Pb(2)-I(3) 3, p.1779

, )-I(4) 3.1294(13) Pb(2)-I(5) 3, Pb, vol.264, issue.23, p.1

, Supporting Information New Type of 2D Perovskites with Alternating Cations in the Interlayer Space, C(NH2)3)(CH3NH3)nPbnI3n+1: Structure, Properties and Photovoltaic Performance

C. Myae-myae-soe and C. C. Stoumpos, 1# Mikaí µí±’í µí±’ ? l Kepenekian, 2 Boubacar Traoré

H. Tsai and W. Nie, Binghao Wang

J. Mohite and . Even,

, Institut des Sciences Chimiques de Rennes (ISCR), UMR

, CNRS -INSA Rennes -Université de Rennes 1, France *Corresponding authors. E-mail: m-kanatzidis@northwestern

, H(2n4) 5327.7 5632

, H(2n5) 5000 1532

, H(1n6) 5000 -600

, H(1n8) 5000 -600

, H(1c1) 966.4 -528

, H(1c3) 846

, H(3c3) -1410.92 5082

, H(2c4) 6349.82 5224

, Ueq is defined as one third of the trace of the orthogonalized Uij tensor

, H(1c2) -6200

, H(2c3) 1181.83 7906

, Ueq is defined as one third of the trace of the orthogonalized Uij tensor