fix scalartype determination in InfiniteMPS constructor

Author: lkdvos

src/states/infinitemps.jl

@@ -193,8 +193,10 @@ function InfiniteMPS(AL::AbstractVector{<:GenericMPSTensor}, C₀::MPSBondTensor
     # initialize tensor storage
     AC = similar.(AL)
     AR = similar.(AL)
-    C = similar(AR, typeof(C₀))
-    ψ = InfiniteMPS{eltype(AL), eltype(C)}(AL, AR, C, AC)
+    T = TensorOperations.promote_contract(scalartype(AL), scalartype(C₀))
+    TC = TensorOperations.tensoradd_type(T, C₀, ((1,), (2,)), false)
+    C = similar(AR, TC)
+    ψ = InfiniteMPS{eltype(AL), TC}(AL, AR, C, AC)
 
     # gaugefix the MPS
     gaugefix!(ψ, AL, C₀; order = :R, kwargs...)
@@ -209,8 +211,10 @@ function InfiniteMPS(C₀::MPSBondTensor, AR::AbstractVector{<:GenericMPSTensor}
     # initialize tensor storage
     AC = similar.(AR)
     AL = similar.(AR)
-    C = similar(AR, typeof(C₀))
-    ψ = InfiniteMPS{eltype(AL), eltype(C)}(AL, AR, C, AC)
+    T = TensorOperations.promote_contract(eltype(AR), eltype(C₀))
+    TC = TensorOperations.tensoradd_type(T, C₀, ((1,), (2,)), false)
+    C = similar(AR, TC)
+    ψ = InfiniteMPS{eltype(AL), TC}(AL, AR, C, AC)
 
     # gaugefix the MPS
     gaugefix!(ψ, AR, C₀; order = :L, kwargs...)