From 259a0243f471de599344ec80aa56e50b49ce2968 Mon Sep 17 00:00:00 2001
From: Duarte Esteves <72316162+DuarteME@users.noreply.github.com>
Date: Mon, 13 Jan 2025 15:48:58 +0000
Subject: [PATCH] Update README.md

---
 README.md | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/README.md b/README.md
index 089c29d..b8d6da8 100644
--- a/README.md
+++ b/README.md
@@ -1,6 +1,9 @@
 # Crystallography by D. M. Esteves (INESC MN/IST-ULisboa)
 This is a Mathematica script to perform algebraic calculations of distances and angles between planes and directions in crystallography.
 
+Requirements:
+Mathematica >= 13.3
+
 Quick guide:
 1. To get started, you should create a list of rules ("params") with your lattice parameters. You can use your favourite units for lengths, as the results will be given in the same units. For angles, please use degrees. Example: for NaCl, a->0.56402 nm.
 
@@ -28,4 +31,4 @@ Quick guide:
 	- 2θ[h,k,l,λ]: gives the 2θ angle associated with the plane with Miller indices (h k l), for a radiation with wavelength λ.
 	- ωminus[h,k,l,m,n,o,λ]: gives the incidence angle associated with the plane with Miller indices (h k l), for a sample with surface (m n o), for a radiation with wavelength λ, in a grazing incidence geometry.
 	- ωplus[h,k,l,m,n,o,λ]: gives the incidence angle associated with the plane with Miller indices (h k l), for a sample with surface (m n o), for a radiation with wavelength λ, in a grazing exit geometry.
-	- ΔφXYZ[a,b,c,d,e,f,g,h,i]: gives the angle between the X=[P]ole/[D]irection, (a b c)/[a b c] and the Y=[P]ole/[D]irection, (d e f)/[d e f] in a sterographic projection where (g h i)/[g h i] is Z=[P]ole/[D]irection of the surface. XYZ can be PPP, PPD, PDP, DDP, DDD, depending on the situation.
\ No newline at end of file
+	- ΔφXYZ[a,b,c,d,e,f,g,h,i]: gives the angle between the X=[P]ole/[D]irection, (a b c)/[a b c] and the Y=[P]ole/[D]irection, (d e f)/[d e f] in a sterographic projection where (g h i)/[g h i] is Z=[P]ole/[D]irection of the surface. XYZ can be PPP, PPD, PDP, DDP, DDD, depending on the situation.